Internet connection using FTTB technology. Which Internet connection technology should you choose? fttb design

Now providers (Internet access service providers) offer several options for wired Internet access. The main technologies for accessing the World Wide Web are ADSL/ADSL2+ and FTTB. How not to get confused in the proposed technologies and choose what you need? This article aims to answer this question. Below we will describe each of the mentioned technologies, taking into account the advantages and disadvantages.

ADSL/ADSL2+ technology

This technology involves transmitting data over regular telephone wires. Because Data transmission occurs in a frequency range different from the frequencies for voice data; transmission of digital data together with voice is possible: i.e. You can talk on the phone and surf the Internet at the same time. To convert information into a form accessible for transmission over telephone wires, a device is used on the subscriber's side - DSL modem, and on the provider’s side, a device called DSLAM is used to reverse convert the information transmitted within the framework of this technology into digital form.

Due to historical circumstances, this technology is “tailored” to transmit data to the subscriber; the transmission speed of the outgoing stream is much lower than the downward one. And this is one of its main disadvantages. For ADSL technology, large providers, such as Rostelecom, MGTS and COMSTAR-Regions (MTS group of companies), offer speeds to the subscriber of up to 8 Mbit/s, and from the subscriber up to 800 kbit/s. In ADSL2+ technology, thanks to improvements, speeds have been increased, but the speed of the outgoing stream also remains low - up to 1 Mbit/s from the subscriber. The speed to the subscriber is up to 24 Mbit/sec.

The quality of communication for this technology largely depends on the quality and length of the telephone line: for example, for the technology, the possibility of providing the service is not guaranteed with a telephone line length of more than 5 kilometers, but with a length of 4 to 5 kilometers maximum speed, on which an ADSL modem can establish a connection with the provider’s station equipment (DSLAM) cannot exceed 2 megabits per second to the subscriber.

Despite the many disadvantages, this technology also has its advantages. These include the absence of the need to run a separate cable into the house if there is a landline telephone, provided that the telephone line is of sufficient quality and there are no errors in the connection circuit of the modem to the telephone socket - extremely high stability and reliability of the connection, many times greater than that which is achievable when connecting via more advanced FTTB technology.

Reliability is associated with the high fault tolerance of DSLAM, as well as the mandatory presence of guaranteed high-capacity power supply at the PBX (on which the provider’s DSLAM is located), which makes the operation of the Internet independent of the presence or absence of light at the point where the provider’s equipment is located. Also, an undoubted advantage of the ADSL family of technologies is the ability to connect to the Internet in private homes.

FTTB technology

FTTB technology stands for “Fiber-To-The-Building”(“Optics to the home”), and means that the provider supplies a fiber optic cable to an apartment building, which then goes into a switch (managed switch) - a device that “divides” the Internet among individual users. As a rule, the switch is installed in the entrance or attic, and a regular twisted pair cable (Ethernet cable used in office buildings) goes from it to the subscribers. local networks).

Depending on the implementation of the technology, the Internet access speed can be up to 10 or 100 Mbit per second. In this case, the throughput speed of the fiber optic channel to the switch can be from 1 to 10 Gbit per second. This technology is currently in use a huge amount providers, both small and very large, such as Beeline, Rostelecom, TTK, COMSTAR-Regions (MTS group of companies).

The qualitative difference between this technology and ADSL technologies is a symmetrical channel, i.e. the upload and reception speeds are equal, which is a big plus for those users who download torrents, upload large files to servers, or have their own website. Also, the advantages of FTTB include the absence of the need for additional equipment - to work, you just need to insert the provider’s cable into the network card of your computer or laptop (you may also need to create a connection).

The main disadvantage of FTTB is the relative low reliability and the dependence of Internet access speed on the number of users connected to a given switch: with a large number of subscribers bandwidth The fiber optic channel supplied to the home switch may not be enough and you will need to expand its capacity, which is not always done on time. The low reliability of FTTB is associated with the low fault tolerance of switches (usually due to the cheapness of the devices used), as well as the fact that they are usually not equipped with uninterruptible power supplies and at the slightest power outage at the point, users are left without the Internet. Another disadvantage is that FTTB technology is not available to users living in private homes.

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MINISTRY OF EDUCATION AND SCIENCE OF THE RUSSIAN FEDERATION

Federal State Budgetary Educational Institution

higher professional education

"KUBAN STATE UNIVERSITY"

(FSBEI HPE "KubSU")

Physics and Technology Faculty

Department of Optoelectronics

GRADUATE WORK

DESIGNING BROADBAND ACCESS USING FTTB TECHNOLOGY

The work was carried out by Kuznetsov Maxim Sergeevich

Specialty 210401 - Physics and optical communications technology

Scientific director

Ph.D. tech. Sciences, Professor Yu. N. Belov

Standards inspector engineer I. A. Prokhorova

Krasnodar 2012

Kuznetsov M. S. DESIGN OF BROADBAND ACCESS USING FTTB TECHNOLOGY. Thesis: 91 pp., 23 figures, 7 tables, 10 sources used.

WIRED COMMUNICATION SYSTEMS, SUBSCRIBER ACCESS, TELECOMMUNICATION CABLES, ACCESS NETWORK DESIGN, FTTB

The object of study of this course work is broadband technology, telecommunication cables.

The purpose of the work is to study the structure of broadband subscriber access networks and their varieties, comparative analysis various types subscriber access, carrying out calculations on the distance of subscribers from active equipment, designing a FTTB network, calculating the main characteristics of the network.

As a result of the thesis, a subscriber access network was designed, the need to increase the transmission speed and length of communication lines when using low-frequency cables was considered. Calculations were carried out on the distance of subscribers from the nearest active equipment.

subscriber access network broadband

Notations and abbreviations

Introduction

1. Subscriber access

1.1 Technologies of the xDSL family

1.2.2 PON technologies

2. Ethernet technologies

2.1 Fast Ethernet

2.2 Gigabit Ethernet

3.3 Calculation of cable parameters

3.3.2 Initial parameters of the cable being calculated

4.2 Equipment selection

4.3 Network planning

4.4 Provision of access services

4.5 Construction along Sormovskaya Street

4.6 Design of cable ducts

4.7 Laying OK in the sewer

4.8 Linear communication structures inside the building

4.9 Power supply

4.10 User equipment

4.11 Losses in the optical communication line

4.12 Economic calculation of the project

4.12.1 Cost of goods

4.12.2 Cost of work

4.12.3 Calculation of payback periods

4.13 Network scalability and development prospects

4.13.1 Step towards new technologies

4.13.2 Conversion to CWDM and PON

4.14 Possibility of using an upgraded UTP cable in the designed network

Conclusion

List of sources used

Application

Notations and abbreviations

	Asymmetric Digital Subscriber Line - asymmetric digital subscriber line

	Asynchronous Transfer Mode - asynchronous data transfer mode
	Broadband Passive Optical Network - broadband passive optical network
	Digital Subscriber Line - digital subscriber line
	Digital Subscriber Line Access Multiplexer - DSL access multiplexer
	Ethernet in the First Mile - Ethernet technology at the last mile
	Ethernet PON - Ethernet passive optical network technology
	Ethernet To The Home - Ethernet to the home
	Fiber To The Building - fiber optic communication line to the building
	Fiber To The Curb - fiber optic communication line to the distribution box
	Fiber To The Home - fiber optic communication line to the home
	Fiber To The x - fiber-optic communication line to point x
	Gigabit Passive Optical Network - passive optical network with possible throughput of up to 2.5 Gbit/s
	Internet Protocol -- Internet protocol
	Optical Line Terminal - optical linear termination
	Optical Network Unit - optical network element
	Passive Optical Networking - passive optical networks
	Very high bit-rate Digital Subscriber Line - ultra-high-speed digital subscriber line
	Wavelength-Division Multiplexing - Wave multiplexing technology
	Digital Subscriber Line -- digital subscriber line, general designation for a range of digital subscriber line technologies
	automatic telephone exchange

Introduction

The choice of one or another strategy for the development of subscriber access networks, with all the variety of subtleties and nuances, for the provider is determined primarily by the economic feasibility of using technologies and the adoption of standards covering a wide variety of areas of telecommunications. For the subscriber, and therefore for the provider, in addition to financial costs, other access properties are of no small importance. These are data transfer speed, multi-service, reliability and quality of services provided. All these, as well as technical and operational and many other factors must be taken into account.

The increase in the capacity of cable systems with the introduction of fiber optical communication lines has reached a qualitatively new level. These days, optical communication systems play a key role. Over time they become cheaper and more accessible. However, as is known, most of the costs when deploying urban networks are spent on laying cable systems. This fact seriously limits the speed at which newer technologies can spread. The current stage of evolution of urban subscriber access networks is experiencing only a partial transition to optical fiber, and at this stage the most pressing issues related to the implementation last mile in the form of copper-core cables, the length of which is about one hundred meters.

In the presented diploma work The issues of designing broadband subscriber access are discussed in detail.

1. Subscriber access

Subscriber access is the user’s ability to exchange various types of information remotely from the source upon request. The final implementation of subscriber access includes a physical environment and devices for receiving, transmitting and processing data. Subscriber access is ultimately characterized by the package of services provided. The most common of them are access to the internet, television and telephony. The service package depends on the capacity of the subscriber line.

1.1 Technologies of the xDSL family

Let's consider a conventional wired access scheme on copper low-frequency communication cables. (picture 1).

1 - central station, 2 - main sections of other directions, 3 - main section, 4 - distribution cabinet,

5 - distribution sections of other directions, 6 - distribution section, 7 - subscriber box, 8 - subscriber wiring laid to other network users, 9 - subscriber wiring, 10 - terminal devices.

Figure 1 - Scheme of constructing subscriber access based on copper cables

A common case is when a copper cable (hundreds of pairs) is pulled from the PBX. This cable is connected to a distribution cabinet, from which cables with an order of magnitude smaller number of pairs diverge in different directions. This cable reaches the subscriber box, from where the pair comes directly to the subscriber via the subscriber wiring. Initially, such lines were intended for telephone communication. With the development of the Internet and the advent of new communication services, these lines began to be used in digital systems data transmission. Their further development led to the emergence of VDSL, ADSL, ADSL2, ADSL2+, SHDSL technologies through the use of in various ways coding and organization of broadband communications.

In local primary communication networks, copper cable of the TPP series is often used. Figure 2 shows theoretical graphs of the dependence of the information transmission speed over the TPP cable on its length under other ideal conditions, for some technologies of the xDSL family.

Figure 2 - Information transmission speeds via the TPP cable, depending on its length

The sources also show similar graphs for ADSL subgroup technologies (Figure 3).

Figure 3 - Information transmission rates for ADSL technologies depending on line length

When analyzing the graphs, it turns out that a two-wire low-frequency copper cable can be effectively used at a distance of up to 6 km, depending on the level of electromagnetic interference, the quality of the cable itself, etc. Due to the mutual influence of pairs, the number of subscribers is limited, since crosstalk will reduce information transfer speed. In practice, about 40% of the total number of pairs can be used. In addition, copper cables age over time, the quality of insulation decreases, and copper corrodes. All these problems increase cable attenuation, contribute to interference, and therefore reduce data transmission speed. Even in the best case, over short distances, the transmission speed of digital information cannot exceed 30 Mb/s. Even this is not enough to ensure the simultaneous operation of several services. To implement television High Quality Bandwidth up to 32 Mbps is required. In addition, there is a growing need to increase the quality and speed of access to resources on the Internet.

1.2 Technologies using fiber-optic lines

Currently, it is possible to implement wired access technologies based on optical fiber. These include FTTx and PON. These technologies can be used simultaneously or in conjunction with many others to solve the last mile problem.

It is worth noting that optical fibers conduct photons and not electrical signals. Almost all problems inherent in metal cable, such as electromagnetic interference, crosstalk (crosstalk) and the need for grounding, galvanic isolation are completely eliminated.

Modern optical emitters in fiber-optic communication systems are capable of switching with a frequency of the order of tens of GHz. Optical fibers have low attenuation (less than 10 dB/km). Thanks to these characteristics, fiber-optic lines have an undeniable advantage over copper-core communication lines. Optical fiber can provide high speed information transfer over long distances.

Technologies of the FTTx family provide for bringing the optical cable to point “x”. They are classified according to the degree of proximity of the subscriber to the fiber delivery point (Figure 4).

Figure 4 - FTTx implementation options

FTTx technologies can also be classified by the method of data transmission from the network hub to the subscriber. FTTB can be interpreted as FTTC and FTTCab, since there is no fundamental difference between them. One of the technologies used in the last mile is xDSL (Figure 5).

1 - central station, 2 - backbone sections of other directions (optical cable), 3 - backbone section (optical cable), 4 - switch with DSLAM, 5 - distribution sections of other directions (copper twisted pairs), 6 - distribution section (copper twisted pairs) pairs), 7 - DSL modem, 8 - Ethernet cable, 9 - terminal devices, 10 - protective distribution cabinet with power supplies, 11 - subscriber’s home or office

Figure 5 - Scheme of building mixed subscriber access using xDSL

In this circuit, the optical cable is connected to the DSLAM. This device is usually installed in a cabinet protected from adverse weather conditions and vandalism, where an uninterruptible power supply is also provided. The section from the cabinet to the subscriber is similar to the section of a traditional DSL line. This scheme is most suitable for implementing FTTC and FTTN, in the case where the distance from the communication center is more than 5 km.

There is another type of mixed access, when a distribution subscriber network is built on the basis of a pre-laid Ethernet local network; switches in the network have one or more optical interfaces through which they connect to other switches or to network devices in a central communication center. Through which Internet access, other subscriber access services and the operation of the entire network are provided.

Mixed access technologies involve bringing optics to the point of concentration. But you can run a fiber optic cable directly to the subscriber, be it an apartment, house or office. This corresponds to the FTTH (Fiber To The House) concept, Figure 6.

1 - central station with an optical transmitter, 2 - backbone sections of other directions (optical cable), 3 - backbone section (optical cable), 4 - optoelectronic modem, 5 - terminal devices, 6 - home or office of the subscriber

Figure 6 - Scheme of building FTTH technology with point-to-point topology

This technology makes it possible to provide individual users with channels with a throughput of more than 1 Gbit/s, while the distance from the communication center to the subscriber can be several tens of times greater compared to DSL.

1.2.2 PON technologies

Optical networks can be divided into two classes - active and passive. There is some active equipment (for example, a regenerator or switch) between the access node and the end user equipment of the active network. IN passive network There is no active equipment, i.e. the network consists only of passive components: fiber optic connectors, splitters and WDM multiplexers. Usually, instead of the full name "passive optical network", the abbreviation PON (Passive Optical Network) is used (Figure 7).

Figure 7 - General structure PON networks

The active equipment at the central office or access point is called an optical line terminal (OLT), and the equipment at the subscriber node is called an optical network unit (ONU). Some of the communication services typically provided by PON networks are also shown in Figure 7. The key link in a PON network is the splitter (passive optical splitter), which is characterized by a splitting factor N. By branching, the optical signal is divided by power into N directions. The number of branches from one fiber can reach 32.

PON is a family of fast-growing, most promising technologies for broadband multiservice multiple access over optical fiber. The essence of passive optical network technology is that the optical signal is branched using passive optical power dividers - splitters. The consequence of this advantage is reduced access system costs, reduced network management required, high transmission range and no need for subsequent upgrades. distribution network.

Of the PON family technologies, 4 types are currently known:

* APON (ATM PON);

* BPON (Broadband PON);

* GPON (Gigabit PON);

* EPON (Ethernet PON).

The problem with FTTH is the high cost of network deployment, since for each subscriber it is necessary to allocate a fiber in the cable; the subscriber’s optical equipment also requires large financial costs. PON technology allows the operator to save on fiber laying, but the problem of equipment price is not solved. Many operators are still trying to use the existing copper cable infrastructure. FTTB technology is becoming the most promising in the coming years, both using EFM and using DSL. The advantages of this concept are that one optical interface can provide access to dozens of subscribers, copper cabling and switching equipment do not require large expenses, and Ethernet network interfaces are available on most computers. It is also possible to organize a local network within apartment building or groups of houses.

For areas with private buildings, FTTN technologies in the form of xDSL, as well as FTTH and PON, are most suitable. Since the subscribers are separated in space over quite large distances. The FTTB scheme is most suitable for areas with high concentrations of apartment buildings, since the maximum possible length of the subscriber communication line is limited to one hundred meters.

2. Ethernet technologies

Ethernet is the most common local network standard today. The total number of networks currently operating using the Ethernet protocol is estimated at several million.

When people say Ethernet, they usually mean any of the variants of this technology, which today also includes Fast Ethernet, Gigabit Ethernet and 10G Ethernet.

In a narrower sense, Ethernet is a network data transfer standard with a speed of 10 Mbit/s, which appeared in the late 70s as a standard of three companies - Digital, Intel and Xerox. In the early 1980s, Ethernet was standardized by the IEEE 802.3 working group and has been an international standard ever since. Ethernet technology was the first technology to offer a shared medium for network access.

Local networks, being packet networks, use the principle of time multiplexing, that is, they divide the transmission medium in time. The media access control algorithm is one of the most important characteristics of any LAN technology, determining its appearance to a much greater extent than the signal encoding method or frame format. Ethernet technology uses the random access method as a medium separation algorithm. And although it can hardly be called perfect - as the load increases, the useful network throughput drops sharply - but due to its simplicity it was the main reason for the success of Ethernet technology.

The popularity of the 10 Mbit/s Ethernet standard served as a powerful stimulus for its development. The Fast Ethernet standard was adopted in 1995, Gigabit Ethernet in 1998, and 10G Ethernet in 2002. Each of the new standards was 10 times faster than its predecessor, forming an impressive hierarchy of speeds of 10 Mbit/s - 100 Mbit/s - 1000 Mbit/s - 10 Gbit/s.

When using Ethernet technologies to provide access services, two main topologies are used (Figure 8 and Figure 9).

Figure 8 - Ring topology

Figure 9 - Mixed topology

To reserve channels and reduce congestion, ring topologies can be used, however, in order to save money, in some cases, a star topology can be used on pre-aggregation switches, but such a topology is not highly reliable.

As can be seen from Figures 8 and 9, the structure of networks follows a hierarchy. As you move away from subscribers, increasingly high-speed connections are used.

2.1 Fast Ethernet

The organization of the physical layer of Fast Ethernet technology is more complex compared to previous standards, since it uses three types of cabling systems:

*fiber optic multimode cable (two fibers);

Coaxial cable, which gave the world the first Ethernet network, is among the permitted data transmission media new technology Fast Ethernet didn't make it. This is a common trend in many new technologies, because over short distances, Category 5 twisted pair cable can transmit data at the same speed as coaxial cable, but the network is cheaper and easier to operate. Over long distances, optical fiber has much higher capacity than coaxial cable, and the cost of the network is not much higher, especially when you consider the high troubleshooting costs of a large coaxial cable system.

Fast Ethernet networks have a hierarchical tree structure built on hubs. The main difference between Fast Ethernet network configurations is the reduction in network diameter to approximately 200 m, which is explained by a 10-fold reduction in the minimum length frame transmission time due to a 10-fold increase in transmission speed compared to a 10-Mbit Ethernet network.

Nevertheless, this circumstance does not really hinder the construction of large networks using Fast Ethernet technology. The fact is that the mid-90s were marked not only by the widespread use of inexpensive high-speed technologies, but also by the rapid development of local networks based on switches. When using switches, the Fast Ethernet protocol can operate in full-duplex mode, in which there are no restrictions on the total length of the network, but only restrictions on the length of the physical segments connecting neighboring devices (adapter-switch and switch-switch).

The physical variants of Fast Ethernet differ from each other to a greater extent than the physical implementations of Ethernet. Here, both the number of conductors and coding methods change. And since the physical variants of Fast Ethernet were created simultaneously, and not evolutionarily, as for Ethernet networks, it was possible to define in detail those sublayers of the physical layer that do not change from variant to variant, and those sublayers that are specific to each variant of the physical environment.

The official 802.3 standard established three different specifications for the Fast Ethernet physical layer and gave them the following names (Figure 13.2);

*100Base-TX for two-pair cable on UTP Category 5 UTP or STP Type 1 shielded twisted pair;

*100Base-T4 for four-pair UTP Category 3, 4 or 5 UTP cable;

The following statements and characteristics apply to all three standards.

*100Base-FX for multimode fiber optic cable with two fibers.

Like any network, Fast Ethernet has limitations on the length of the communication line (Table 1).

Table 1 - Maximum segment length for various standards

2.2 Gigabit Ethernet

The main idea of the developers of the Gigabit Ethernet standard was to preserve as much as possible the ideas of classical Ethernet technology while achieving a bit speed of 1000 Mbit/s.

Since when developing a new technology it is natural to expect some technical innovations that follow the general trend of development of network technologies, it is important to note that the Gigabit Ethernet standard, like its slower counterparts, does not support at the protocol level:

*quality of service;

*excessive connections;

*testing the performance of nodes and equipment (with the exception of testing port-to-port communication, as is done in Ethernet 10Base-T, 10Base-F and Fast Ethernet).

All three of these properties are considered very promising and useful in modern networks, and especially in networks of the near future.

The following types of cables provided by the 802.3z standard can be used as a physical data transmission medium for Gigabit Ethernet:

*single-mode fiber optic cable;

*multi-mode fiber optic cable 62.5/125;

*multimode fiber optic cable 50/125;

*shielded digital copper cable.

Applicable to subscriber access networks, Ethernet technologies can be used in a hierarchical manner, when low-speed communication channels are combined into high-speed data streams. Thanks to optical fiber, networks can be significantly removed from central communication centers.

3. Twisted pair in Ethernet networks

Twisted pair is a type of communication cable that consists of one or more pairs of insulated conductors twisted together (with a small number of turns per unit length) to reduce mutual interference during signal transmission, and covered with a plastic sheath. Twisted pair cable is used in telecommunications and computer networks as a network media in many technologies such as Ethernet, ARCNet and Token ring.

Currently, due to its low cost and ease of installation, it is the most common for building local networks.

Depending on the presence of protection - an electrically grounded copper braid or aluminum foil around the twisted pairs, the types of this technology are determined:

*unshielded twisted pair (UTP -- Unshielded twisted pair)

*shielded twisted pair (STP -- Shielded twisted pair)

*foil twisted pair (FTP -- Foiled twisted pair)

*foil shielded twisted pair (SFTP -- Shielded Foiled twisted pair)

In some types of shielded cable, protection can also be used around each pair, individual shielding. Shielding provides better protection from electromagnetic interference, both external and internal, etc. The entire length of the screen is connected to a non-insulated drain wire, which unites the screen in case of division into sections due to excessive bending or stretching of the cable.

In addition to this, a single-core stranded cable is used. In the first case, each wire consists of one copper core, and in the second - of several.

A single-core cable does not require direct contact with connected peripherals. That is, as a rule, it is used for laying in boxes, walls, etc. followed by termination with sockets. This is due to the fact that copper strands are quite thick and with frequent bending they quickly break. However, such conductors are ideally suited for “cutting into” the connectors of socket panels.

In turn, a multi-core cable does not tolerate “cutting” into the connectors of socket panels (thin cores are cut), but behaves well when bent and twisted. Therefore, multi-core cable is used mainly for the manufacture of patch cords (PatchCord), connecting peripherals to sockets. In addition, stranded wire has less resistance to high-frequency signals (Skin effect).

Cables based on twisted pair copper unshielded are divided into 5 categories according to their electromechanical properties.

Category 1 cable is used in cases where data transfer speed requirements are minimal. It is typically used for analog and digital voice and low-speed data transmission.

Category 3 cable was standardized in 1991. Then the Standard for Telecommunications Cabling Systems for Commercial Buildings (EIA-568) was developed, and subsequently the EIA-568A standard was created on its basis. This standard defines the electrical characteristics of Category 3 cables at 16 MHz, allowing this cable to be used for high-speed networking applications. Category 3 cable is designed for both data and voice transmission. The twisting pitch of the wires corresponds to three turns per 30.5 cm. The majority of cable systems in office buildings, through which voice and data are transmitted, are built on the basis of this cable.

Category 4 cable is an improved version of the previous category. This cable must withstand tests at a signal transmission frequency of 20 MHz, while providing good noise immunity and low signal loss. This category is well suited for systems with extended distances of up to 135 meters, as well as Token Ring networks with a throughput of 16 Mbps. However, in practice it is almost never used.

Category 5 cable is specifically designed to support high-speed protocols. Their characteristics are determined in the range up to 100 MHz. Most high-speed standards are oriented towards Category 5 cable. It supports protocols with a data transfer rate of 100 Mbit/s FDDI with the physical standard TP-PMD, Fast Ethernet, 100VG-AnyLAN and faster ATM protocols with a speed of 155 Mbit/s, as well as a Gigabit Ethernet option with a speed of 1000 Mbit/s. A twisted-pair version of Gigabit Ethernet using 4-core UTP cable became the standard in 1999. Category 5 cable has replaced Category 3, and large building cabling systems are now built using this type of cable in combination with fiber optic cable.

UTP cables are available in 2-pair and 4-pair versions. Each pair of such cable has its own twist pitch and a specific color. In the 4-pair version, two pairs are for data transmission and two more are for voice transmission.

To connect the cables, RJ-45 sockets and plugs are used, which are eight-pin connectors and look similar to telephone connectors.

The main purpose of this cable is to support high-speed protocols over cable sections longer than Category 5 UTP cable, the maximum segment length of which should not exceed 100 meters. Category 7 cable is hardly advisable for use: the cost of a network based on it is close to the cost of a fiber-optic network, and the characteristics of fiber-optic cables are higher. Therefore, it is likely to gradually disappear in the near future, remaining only in the history of cable development.

Cables based on shielded twisted pair STP protect the transmitted signals well from external interference. The grounded screen used in this type of cable complicates installation, as it requires high-quality grounding and increases the cost of the cable itself. Shielded cable is used for data transmission only.

3.1 Features of electrical signal transmission

Any telecommunication system consists of one or more symmetrical circuits, a typical section diagram of which is shown in Figure 10.

Figure 10 - Equivalent electrical diagram symmetrical circuit section

This circuit is also a low-pass filter circuit. This causes a limitation in the data transmission speed of all telecommunication cables. If there are several circuits in the cable, then you should pay attention to the presence of mutual influence of the lines on each other (Figure 11).

1 - transmitter, 2 - receiver, 3 - symmetrical pair, 4 - influencing conductor

Figure 11 - Principle of mutual influence

where C is capacity, F;

Relative dielectric constant of the medium;

0 - electrical constant, F/m;

S - surface area, m2;

r - distance between conductors, m.

If the distance r1 is not equal to the distance r2 (Figure 11), then the capacities will be different. It is worth adding that the influence is exerted along the entire length of the cable line; moreover, the number of symmetrical pairs in the cable can be on the order of tens or hundreds. This problem is especially relevant for xDSL family technologies. In order to equalize the average distance along the cable length between the conductors of adjacent pairs in the cable, and therefore the corresponding capacitances inside the cable and, therefore, get rid of mutual influences, each pair is twisted, and with a different twisting pitch. Thus, the average distance between pairs is equalized. This method of solving the problem of mutual interference is applied to VDSL and a series of Ethernet technologies.

3.2 Design features

In Metro Ethernet networks in the subscriber wiring section, as a rule, UTP cables of the fifth category are used. Such cables consist of four copper conductors coated with polyvinyl chloride insulation (PVC) or polyethylene insulation. The cores are twisted together according to the principle of double pair twisting, which reduces electromagnetic influences. Thus, the strands twisted in pairs form twisted pairs. They have different twist pitches to equalize the capacitive components of the cable. Next, the twisted pairs are twisted together with a pitch tens of times larger than with pair twisting. This entire structure is surrounded by a polymer shell made of the same materials as the individual conductors. Possible scheme A cross-section of such a cable is shown in Figure 12.

1 - copper conductor, 2 - conductor shell

Figure 12 - Possible cable cross-section

In accordance with the FastEthernet - 100BASE-TX, IEEE 802.3u standard on copper cable, two twisted pairs are sufficient to transmit data at a speed of 100 Mbit/s, and, other things being equal, the operation of a transmission system with a cable line length of up to 100 meters is guaranteed , when using UTP category 5 cable. But in order to further increase the throughput of the local network and move to the 1000BASE-T IEEE 802.3ab standard, where the speed is 1 Gbit/s, a category 5e cable with four twisted pairs is laid in advance. Also, free pairs can be used to connect telephone communications running over IP. The analog signal transmitted over the free pair is digitized, encoded, and encapsulated in an Ethernet frame.

As is known, it is advisable to use ETTH technology over twisted pair with FTTB in densely populated areas. From this point of view, it is most effective to install the networks in question in apartment, multi-story, and nearby buildings. It is also convenient that the houses have power supply for active equipment and technical floors where it is possible to place switches, uninterruptible power supplies, and so on.

Often when laying fiber cable to a switch on the technical floor in apartment building, the maximum possible length of a twisted pair cable, in this case 100 m, is not enough to route the telecommunication cable to subscribers more distant from the switch. This issue can be resolved in two ways. One solution involves installing switches at several points inside the building, which will significantly increase financial and time costs. Another solution is to improve telecommunication cables. This is achieved by changing design parameters and manufacturing materials.

3.3 Calculation of cable parameters

3.3.1 Principle of calculation of main parameters

The primary parameters of a symmetrical communication line include: capacitance C, inductance L, conductor resistance R, and insulation conductivity G. The arrangement of these elements is shown in Figure 9. The primary parameters are inherent in a certain non-zero line length; they increase with increasing cable length.

Since the insulated conductors are twisted together, we enter a parameter that will characterize the ratio of the length of the conductors to the length of the cable:

where D is the average diameter of the cable strand, mm;

h - twist pitch, mm.

The average cable strand diameter is calculated using the formula:

where dп is the diameter of the group, mm;

n is the number of groups in central irrigation.

In the case under consideration, the number of groups is two, the group is a twisted pair. The central twist is the only one. The diameter of a group is nothing more than the average width of space occupied by a pair. In case of pair twist:

where d is the diameter of the insulated conductor mm.

Let us introduce a coefficient that takes into account the proximity of conductors of adjacent conductors in the case of double pair twisting:

where ddp is the diameter of double pair twist, mm;

d - diameter of the insulated conductor, mm;

dg - diameter of bare conductor, mm;

a is the distance between the centers of the conductors, mm.

In the case under consideration, the distance between the centers of the conductors is equal to the diameter of the insulated conductor. The diameter of the double pair twist is calculated using the formula:

Using the above parameters you can calculate the capacity:

where r is the radius of the bare conductor.

To calculate the primary parameters L, R, it is necessary to know the special Bessel functions. For the frequencies under consideration they have the following form:

where r is the radius of the bare conductor, mm;

k - eddy current coefficient, mm-1.

Since the radius of the bare conductor is fixed, the eddy current coefficient depends on the frequency. The product and the bare conductor radius for copper can be represented as a function whose argument is frequency:

where f is frequency, Hz.

Thus, one can think of Bessel functions as functions of frequency.

For this reason, inductance is also represented as a function of frequency, which has the form:

where µ is the relative magnetic permeability of the medium;

Q(f) is the Bessel function (8).

For copper µ=1. The total inductance is the sum of external and internal

The conductivity of the insulation also depends on the frequency:

where Riz is the specific volume electrical resistance insulation, Ohm km;

tan - dielectric loss tangent.

The dielectric loss tangent of the shell material depends on the frequency. A typical relationship is shown in Figure 13

Figure 13 - Theoretical dependence of the dielectric loss tangent on frequency

The active cable resistance of the circuit is calculated using the following formula:

where R0 is the resistivity of the conductor, Ohm/km;

Rm - resistance due to additional losses due to eddy currents, Ohm/km;

p - coefficient taking into account the type of twist (with double pair p = 2);

F(f), E(f), H(f) are special Bessel functions (9), (10), (11), respectively.

In low-pair cables, as well as in cables without additional metal structures, which are the ones under consideration, the resistance Rm is taken equal to zero.

The resistivity of a copper conductor is determined by the following formula:

where c is the resistivity of the metal, Ohm mm2/m

Q(f) is the Bessel function (8).

For copper c=0.0175.

Finally, collecting the data obtained, we can write the attenuation function as a function of frequency:

where f is frequency, Hz;

R(f) - function of resistance due to active losses from frequency, Ohm/km;

G(f) - function of insulation conductivity versus frequency, S/km;

L(f) - function of inductance versus frequency, H/km;

C is the capacity of the symmetrical cable circuit, F/km.

3.3.2 Initial design parameters of the calculated cable

The source shows the design characteristics of the cable traditionally used in local networks - UTP category 5e:

Diameter of insulated conductor d=0.9 mm.

Diameter of bare conductor dg=0.51 mm.

The conductor material is copper.

The conductor sheath material is high density polyethylene.

In accordance with GOST 16337-77, dielectric loss tangent: tan=3·10-4 at a frequency of 1 MHz. The source shows tgд=14·10-4 at a frequency of 550 kHz, and tgд=2·10-4 at a frequency of 10 kHz. From Figure 13 and the obtained values of the dielectric loss tangent it is clear that the frequency corresponding to the maximum point is less than 1 MHz. This means that at frequencies above 1 MHz, with increasing frequency, a decrease in the tgd value is observed. Consequently, if we take tan = 3 · 10-4 over the entire frequency range, then the calculated attenuation at frequencies above 1 MHz will slightly exceed the actual values, which will provide additional energy reserve for the system in the future. In the source, the relative dielectric constant of the medium? with the best technology for polyethylene production is 1.2. Specific volumetric electrical resistance of insulation Riz in the range from 1015 to 1017 Ohm km. Let us take into consideration the worst case scenario, when Riz = 1015 Ohm km. The twist pitch, in accordance with, ranges from 12 to 32 mm. For calculations we use a typical case when the pitch h = 24 mm. Let's summarize all the initial data in Table 2.

Table 2 - Initial characteristics of the calculated cable

3.3.3 Calculation of primary parameters and cable attenuation

The above methodology was applied to the initial data; as a result of the calculations, graphs of the dependence of the electrical circuit parameters on frequency were obtained; they are shown in Figures 14, 15, 16, 17.

Figure 14 - Dependence of inductance on frequency

Figure 15 - Dependence of characteristic impedance on frequency

Figure 16 - Dependence of the active resistance of the conductor on frequency

Figure 17 - Dependence of the active resistance of the conductor on frequency

As can be seen from the graph, as the frequency increases, the internal inductance decreases and the dependence decreases. At high frequencies, the total inductance is close to the external value.

The insulation conductivity function increases linearly. In reality, this dependence is close to a linear law, but is not such, since the dependence of tgd on frequency is not linear.

The attenuation graph in a symmetrical cable circuit in the frequency range from zero to one hundred MHz is shown in Figure 18

Figure 18 - Dependence of the attenuation of a symmetrical cable circuit on frequency.

Let's enter the values of the calculated parameters at a frequency of 100 MHz in Table 3

Table 3 - Calculated parameters

The obtained attenuation result complies with the requirements of the TIA/EIA-568-A and ISO/IEC 11801 standards. However, the issue of reducing attenuation as much as possible is still relevant.

Much depends on the quality of the insulation and conductor. By changing materials, you can achieve both a decrease and an increase in attenuation. It is also obvious that as the twist pitch decreases, the attenuation will increase, since the ratio of the length of the conductor to the length of the cable will increase.

3.3.4 Dependence of attenuation on conductor diameter and sheath thickness

With fixed insulation properties, the question of reducing the attenuation of the cable chain by changing geometric parameters cable, namely the diameter of the insulated core and the diameter of the bare conductor.

Let us fix the frequency f at one hundred MHz, and transform the above expressions and frequency functions into functions of the diameter of the bare conductor at a constant thickness of the insulated conductor (d = 0.9 mm). At the same time 0

Figure 19 - Dependence of the attenuation of a symmetrical cable circuit on the insulation diameter.

From this graph we can draw an important conclusion that there is an optimal thickness of conductor insulation. In order to find the minimum point, it is necessary to take the derivative b?(dg)=(db)/(ddg). The function b?(dg) is also presented in Figure 17. With a diameter dg=0.31 mm, the function b?(d) becomes zero. This means that at this diameter there is a minimum attenuation. The attenuation at d=0.9 mm and dg=0.31 mm was 175.94 dB/km.

Having performed a similar operation for a number of other diameters of the insulated conductor, we will find for them the values of the optimal diameters of the bare conductor and enter the results in Table 4.

Table 4 - Optimal values for pair design

Diameter of insulated conductor d, mm.	Diameter of bare conductor, dg, mm.

The optimal dependence graph is presented in Figure 20.

Figure 20 - Optimal dependence of the diameter of the insulated conductor on the diameter of the bare conductor.

The resulting dependence is close to linear, so from these points it is possible to restore a linear function. So, the optimal dependence analytically looks like this:

The second term in this formula can be neglected in some cases.

If we take this dependence into account, we can obtain a graph of the attenuation function versus the diameter of the bare conductor, provided that the diameter of the insulated core is selected optimally. The result of this calculation is shown in Figure 21.

Figure 21 - Dependence of attenuation on the diameter of the insulated conductor with an optimally selected diameter of the insulated conductor

The minimum point of this function corresponds to the conductor diameter dg=2.1 mm. In this case, the diameter of the insulated conductor must be 6.144 mm. Thus, increasing the conductor diameter to 2.1 mm leads to a decrease in attenuation. with a further increase in diameter, an increase in attenuation is observed.

3.3.5 Assessment of the possibility of extending the communication line with increasing conductor diameter

For Fast Ethernet technology, the maximum attenuation of a twisted pair cable is 220 dB/km. For a cable with insulation parameters corresponding to the data from Table 2, a bare conductor diameter of 1 mm and according to the graph in Figure 21, the attenuation was 85.8 dB/km. The result is more than 2.5 times less than the attenuation limit for Fast Ethernet. This means that it is possible to extend the communication line by more than 2.5 times. The maximum permissible length of a UTP cable of the fifth category, with an attenuation at a frequency of 100 MHz of no more than 220 dB/km, between two Fast Ethernet interfaces, is 100 m. By increasing the diameter of the bare conductor to 1 mm, it is possible to obtain a maximum communication line length of more than 250 m. Thus, when it comes to the joint use of FTTB and ETTH technologies, savings can be achieved when deploying an Ethernet network by reducing the cost of optical interfaces, cabinets for active equipment, power wiring, and optical cables.

For an ADSL line, in accordance with c, the attenuation of a symmetrical circuit of a TPP type cable, at the upper frequency of 2 MHz, is 23.85 dB/km. Moreover, the diameter of the conductor in this cable is 0.5 mm. For a cable with insulation parameters and twist pitch corresponding to the data from Table 2, a bare conductor diameter of 1 mm and an insulated conductor diameter calculated from expression (18), at a frequency of 2 MHz, the attenuation, according to calculations, was 11.71 dB/km. The attenuation of the calculated twisted pair is approximately 2 times less. This means that a DSL subscriber access line, when using a 4-core UTP cable with an attenuation of 11.71 dB/km at a frequency of 2 MHz, can operate with the same efficiency as a TPP-based DSL line, with a communication line length that is 2 times longer.

The calculations made it possible to find the optimal attenuation parameters for a twisted pair cable; however, a cable made using this principle will be several times thicker than traditionally used cables. Its weight will also exceed reasonable limits, so the manufacturer needs to find not only the optimal cable from the point of view of meeting the conditions of minimum attenuation, but also from the point of view of maintaining optimal weight and dimensions. Increasing the diameter of the conductor gives a noticeable reduction in attenuation. Especially at high frequencies.

4. Access network design

The design of a multiservice network based on FTTB technologies using Ethernet is being carried out in the Komsomolsky microdistrict of the city of Krasnodar.

Krasnodar (founded in 1793; until 1920 - Ekaterinodamr; received city status in 1867) is a city in the south of Russia, located on the right bank of the Kuban River, at a distance of 120-150 kilometers from the Black and Azov Seas. Administrative center of the Krasnodar region. A major economic and cultural center of the North Caucasus and the Southern Federal District; the historical center of the political-geographical region of Kuban. Unofficially, it is often referred to as the “capital of Kuban”, as well as the “southern capital of Russia”.

The design area is located in the eastern part of the city and is limited from the south and east by the Karasunov chain of lakes, from the west by Tyulyaeva Street, and from the north by Uralskaya Street. The area extends from west to east along Sormovskaya Street. A map of the area in question is given in Appendix B.

4.1 Design feasibility

Most of the houses in the area already have broadband access using the technology in question, however, on the south side of Sormovskaya Street there is currently active development of areas adjacent to the lakes; there are also completed houses that do not have a FTTB connection. The project covers 12 houses. These houses are the most distant from the automatic telephone exchange, located at Tyulyaeva Street, building 4.

A cable duct was laid from the telephone exchange throughout the area, originally intended for copper-core telephone communication cables. The cable duct is also suitable for laying optical communication cables. Most of the cable duct has already been laid.

The task of connecting houses is:

In the construction of the missing cable duct,

In the construction of shafts and cable ducts inside connected buildings,

In laying optical cable to all connected buildings,

In laying copper-core communication cables in the distribution area,

In installing equipment on the PBX (aggregation level),

Installation of equipment in connected houses

4.2 Equipment selection

Most of the providers available in Krasnodar today can offer a maximum Internet access speed of about 16 Mbit/s. Due to the constant growth in the needs of subscribers, as well as with the introduction of HD-TV services, it is necessary not only to ensure a maximum speed exceeding the existing one, but also to leave a “reserve” for increasing the speed.

Most of the buildings in which FTTB networks are to be built have 16 floors and each floor has an average of 4 apartments (for one entrance or section). Thus, when using switches with 24 ports, it is necessary to install 2-3 such switches in each entrance. To build a multiservice network, it is advisable to use the widespread and proven third-level Ethernet access switches QSW-2900-24T-AC from Qtech. The switches have 24 10/100BaseT ports for transmitting information over electrical cables and two Gigabit optical trunk ports, which can be used to form Gigabit rings or for direct communication with a PBX. This means that in such a network, under other satisfactory conditions, three main services can be provided simultaneously. These are HD-TV with speeds of up to 12 or 20 Mbit/s, depending on the video signal encoding method, telephony services with speeds of up to 80 kbit/s, depending on the codec used, as well as Internet access services with a wide range of tariffs plans. These services form the Triple Play concept.

...

March 2012

J'son & Partners Consulting presents brief results of a study of the Russian and global markets for fixed access networks based on the results of their development in 2011.

To assess the general situation on the market, data from such sources as interviews with representatives of operating companies, data from foreign information sources, reports and press releases of Internet providers, as well as J’son & Partners Consulting’s own market models were used.

General characteristics of the broadband access market in Russia

According to J'son & Partners Consulting, by the end of 2011, 39% of households (hereinafter referred to as households) in Russia (21.7 million) had broadband Internet access, of which approximately 1.5% were connected using FTTH technology (PON architecture) .

Rating of countries by the number of “home” broadband connections

At the end of 2011, the leader in the number of broadband subscribers is China, which has 155 million connected households. Italy closes the top ten with about 16 million connections. Over the past year, Russia has risen from 7th to 6th place, ahead of England by almost a million subscribers.

Basic access network technologies

The J"son & Partners Consulting study focuses on the three most common groups of technologies:
- FTTH (usually the xPON family of technologies is used)
- FTTB
- ADSL and ADSL 2+

GPON

Economically, PON technology is more suitable for “carpet” coverage than for spot installations. Using GPON technology, it has become possible to provide Internet access at speeds of up to 50 Gbit/s or more. The length of the fiber optic cable from the network node to the consumer can reach 20 km (more than 90% of US households satisfy this condition). At the same time, developments are underway that will increase the distance to 60 km. The technology is based on the promising G.984.4 standard, which is constantly being improved to add new services and interfaces to the PON system.

FTTB

Active optical network technology FTTB is the main competitor to passive FTTH networks today and in the medium term. This technology currently satisfies the needs of users and is widely used both in Russia and abroad. FTTB technology, in combination with FastEthernet, provides an optimal balance in terms of quality, throughput and costs for network construction, and, unlike PON technology, is more profitable for point-to-point connections.

ADSL 2+

According to J’son & Partners Consulting, ADSL 2+ remains the dominant technology for building broadband access networks for traditional operators. The technology was developed to expand the capabilities of ADSL technology approved by the ITU in 1999. At the moment, networks built on ADSL 2+ are deployed in many countries around the world, however, the technology is gradually becoming outdated and in the near future will no longer be able to satisfy the growing needs of subscribers in terms of information transfer speed. The main advantages of this technology are the low cost of network deployment, including the low cost of subscriber devices (worldwide average - $40), as well as the ability to install subscriber devices as subscriber requests are received.

Penetration of access network technologies

There is no broadband access technology in the world that is clearly recognized as the most effective. Traditional operators in many countries still operate copper access networks with asymmetric data transmission technology - ADSL.

Among optical access networks, technology preferences in different countries may differ diametrically. Among the countries of the world, the highest penetration of FTTH technology was recorded in the UAE - 55%. Next come Japan and South Korea - 26% and 16%, respectively. Russia lags noticeably behind in this indicator - penetration is approximately 0.5%.

FTTH technology dominates in the UAE, Norway, Slovenia, Latvia, Denmark, Portugal, the Netherlands, Malaysia, Italy, Canada and Romania.

FTTB technology dominates in South Korea, Hong Kong, Taiwan, Russia, Bulgaria, Estonia, China, Finland, Czech Republic, France, Ukraine and Turkey.

In other countries, FTTB and FTTH divide the market approximately in half.

There is no consensus in the world about the best standard of the xPON family. There are at least three variants of passive optical networks in the United States. Europe and Japan focus on common but different architectures.

All Russian operators using passive optical access networks have chosen GPON (G.984.4 standard).

Access network equipment

During the period from the beginning of 2008 to the end of 2011, according to J"son & Partners Consulting, about 78 million ports of subscriber devices (ONT/ONU) of all standards were released in the world.

Of the total ONT/ONU output of 78 million, about 59 million comply with the EPON/GEPON standard (IEEE 802.3ah). The main consumers of these devices are operators in Southeast Asia and, above all, Chinese Internet providers.

About 18 million more terminals (i.e., less than a third of GEPON) comply with the GPON standard (ITU-T G.984.1-G.984.3). The main consumers of these devices are operators in North America and Europe (in approximately equal quantities).

ONT/ONU of other standards (for example, BPON) are produced in extremely small quantities.

Regional differences in FTTH architecture are determined by the historical background or characteristics of the region. Thus, on the North American continent, PON architecture is predominantly used. This is due to the fact that the development of FTTH in this region began much earlier than in Europe and was due to the development of cable television networks.

Development of GPON in the Russian broadband market

In general, the share of xPON in the Russian fixed broadband market at the end of 2011 was extremely small: 1.5% of all broadband connections. In the technological structure of development of the Russian market, the share of FTTB and PON technologies will increase by an average of 4% per year, and by 2015 their share will be about 65% of all broadband connections in Russia.

The first Russian operator to begin the construction and development of fiber optic networks to the apartments of potential users based on GPON technology is Rostelecom. Using this technology, the operator connected about 300 thousand subscribers (approximately 3% of the total base).

Rostelecom remains the main consumer of xPON technology in the short and medium term. Plans for large-scale implementation of xPON access networks have at least four macro-regional branches (Center, North-West, Urals and Siberia). Three macro-regional branches (Volga, South and Far East) have not published specific plans for this technology.

(¹From an interview with a top manager of TTK: “We use FTTB technology as the main one, but we are also looking at FTTH, we have even created several experimental zones. This technology has several varieties, in particular GPON, we are looking at all of this. But also FTTB satisfies the needs of the subscriber, I think, for many years to come, 10-20 Mbit/s per household is a lot of speed.")

Until 2009, the largest telephone operator in Europe, MGTS, was also known as the largest Internet provider in Russia using ADSL technology.

In 2010, OJSC MGTS began developing an access network using passive fiber-optic technologies, and in May 2011 began its construction. The active introduction of fiber-optic GPON technology in new buildings and the switching of subscribers to individual lines had a significant impact on the increase in the number of Internet users. The company plans to 100% “glaze” Moscow households. The operator states that subscriber ONT will be provided free of charge, but the operator does not provide information about the sources of financing for this promotion.

In April 2011, a competition was announced for the supply of ONU terminals for this project. Only six vendors were allowed to participate in the competition. The volume of supplies declared is unprecedentedly large: 4.4 million devices, i.e. one in each Moscow household.

In 2012, the company will continue to expand the range of telecom services based on GPON and will introduce a number of tariff plans with a wide selection of speeds.

Detailed research results are presented in the full version of the report
“Review of Fixed Access Network Technologies, 2011”²

(² J’son & Partners Consulting reserves the right to revise, clarify and adjust the estimates given in the report based on new data that can be obtained as part of the ongoing monitoring of the fixed access network market.)

The newsletter was prepared by J"son & PartnersConsulting. We make every effort to provide factual and forecast data that fully reflects the situation and is available at the time of publication of the material. J"son & PartnersConsulting reserves the right to revise the data after the publication of new information by individual players official information.

_______ _____________________________________________

1. Introduction
2. Classification and systematization of technologies
3. Technology overview
4. General characteristics of the broadband access market in Russia
4.1. Market volume and dynamics
4.2. Market structure by access technologies
4.3. Broadband providers
4.3.1. Leading providers
4.3.2. Dynamics of the number of users of leading providers
4.3.3. Comparison of socio-demographic user profiles of leading providers
5. Comparative analysis of Internet access technologies (FTTx, ADSL, DOCSIS) by breakdown
by federal districts

5.1. Average monthly user costs for wired broadband access
5.2. Average Internet speed
5.3. Average monthly volume of traffic consumed
5.4. World market for Internet access networks
6. Manufacturers of equipment for access networks
7. Analysis of the competitive advantages of Russian providers
8. SWOT analysis of the most promising technologies (GPON, FTTB, ADSL 2+)
9. Marketing analysis of fixed access network technologies
9.1 World market
9.1.1. Fixed Access Player Profiles
9.1.2. Access networks of global operators
9.1.3. Manufacturers of equipment of various xPON standards in the world
9.1.4. Shares of manufacturers in global ONT/ONU production
9.2. Russian market
9.2.1. Development plans for xPON networks of the largest national operators
10. Social and economic policy of the state in the field of telecommunications and computer science,
regulator position
11. Development of fixed access networks until 2015
12. Conclusion

Trends J"son & Partners Consulting. Electronic payment systems. Trends. Drivers

Multiservice network technologies

From 50% to 80% of funds are invested in the access network, so the correct choice of technologies and network options is extremely important. The following are factors influencing the choice of one or another subscriber access technology:

Connection cost per subscriber.

Ease of connection is a factor that determines the availability of connection for subscribers and the speed of connection of subscribers.

Sufficient bandwidth or data transfer speed for the subscriber.

Ensuring the required quality of customer service.

Existing cabling infrastructure - coaxial cable, twisted pair, telephone wiring, optical fiber, etc.

At the design stage, it was decided to use FTTB subscriber access technology because it meets all the above requirements and is optimally suited for the implementation of the assigned tasks.

Fiber To The X technology (Optical fiber to...) is a concept that describes a general approach to organizing the cable infrastructure of an access network, in which an optical fiber reaches a certain location (point “x”) from the communication center, and then a copper cable reaches the subscriber. (an option is also possible in which the optics are laid directly to the subscriber device).

So FTTx is just a physical layer. However, in fact, this concept also covers a large number of channel and network level technologies. Inextricably linked with a wide range of FTTx systems is the ability to provide a large number of new services.

The FTTx family includes different types of architectures:

FTTN (Fiber to the Node) - fiber to the network node;

FTTC (Fiber to the Curb) - fiber to a neighborhood, block or group of houses;

FTTB (Fiber to the Building) - fiber to the building;

FTTH (Fiber to the Home) - fiber to the home (apartment or separate cottage).

Experts are clearly in favor of FTTH solutions; they compare the life cycle of investments in any access technology and the correlated increase in access channel capacity requirements. The analysis shows that if the technical solutions that form the basis of the network access segment today turn out to be unable to provide a speed of 100 Mbit/s in 2013-2015, then obsolescence of the equipment will occur before the end of the investment cycle.

Of all the FTTx options, it provides the most bandwidth;

this is a completely standardized and most promising option;

FTTH solutions provide mass service to subscribers at a distance of up to 20 km from the communication center;

they can significantly reduce operating costs by reducing the area of technical premises (needed to accommodate equipment), reducing energy consumption and the actual costs of technical support.

There are two commonly used types of FTTH network organization: based on Ethernet technology and based on PON technology.

Gigabit Ethernet technology is an extension of IEEE 802.3 Ethernet that uses the same packet structure, format, and support for CSMA/CD, full duplex, flow control, and more, while providing a theoretical tenfold increase in performance. Since Gigabit Ethernet technology is compatible with 10Mbps and 100Mbps Ethernet, easy migration to this technology is possible without investing large amounts of money in software, cabling and personnel training

As in the Fast Ethernet standard, there is no universal signal encoding scheme in Gigabit Ethernet; 8B/10B encoding is used for the 1000Base-LX/SX/CX standards, and a special extended line code TX/T2 is used for the 1000Base-T standard. The encoding function is performed by the PCS encoding sublayer located below the GMII independent interface environment. 1000Base-T is a standard Gigabit Ethernet interface for transmission over Category 5 and higher unshielded twisted pair cables over distances of up to 100 meters. All four pairs of copper cable are used for transmission, the transmission speed over one pair is 250 Mbit/s. It is assumed that the standard will provide duplex transmission, and data on each pair will be transmitted simultaneously in two directions at once - double duplex

FTTB subscriber access technology

FTTB technology (Fiber to the Building) is by far the most popular broadband network construction technology in Russia. The widespread use of FTTB was facilitated by lower prices for optical cable (OC), the emergence of cheap optical receivers, transmitters and optical amplifiers (OA). The use of optics in FTTB allows the use of fast Metro Ethernet technology for data transmission, eliminates the need to ground the support cable, eliminates equipment failure from static electricity, and facilitates coordination of the deployed network in supervisory authorities.

The FTTB network built using this technology is two overlay networks: one for analogue cable television services, the other for data transmission services. They are united by the use of various fibers in the same OCs in sections of the highway and in the distribution networks of second-level nodes. Otherwise, unlike DOCSIS, when using FTTB all equipment is strictly specialized: either TV transmission or data transmission, and if one equipment fails, the other service does not suffer.

Fiber optic access networks currently being deployed are based on a variety of architectures and technologies. Carefully designed standards for these technologies and the availability of the necessary equipment mean that service provider networks can be deployed without significant risk. The success of their activities is an incentive for the dynamic development of this industry. It is safe to assume that competitive pressures from this type of network will encourage large telecom operators to invest in fiber access networks.

The topology of the network built using FTTB technology is shown in Appendix B.

The only difference between FTTB is the replacement of optical nodes of the GVKS with “second-level nodes” (amplifier points) and the distribution network cables from coaxial cable to optical. The headend and home distribution network do not require changes when upgrading, and the backbone may only require an increase in the number of optical fibers. Based on the above, in FTTB networks the amount of installed optical fiber and installed optical receivers is increasing.

State educational institution

higher professional education

Volga State University of Telecommunications and Informatics

Department of Communication Lines and Measurements in Communications Engineering

Course work

in the discipline "Design and construction of fiber-optic communication lines"

TECHNOLOGY DESIGNFTTB/ FTTH

Completed by students gr. FO-91

Inkin I. I.

Sedyshov V.

Sorokin S.

Knyazev I.

Head Andreev R.V.

Samara 2012

1. Organization of an optical access network

1.1 Problem statement

In Russia, there is growing interest in the deployment of access networks with the ability to provide subscribers with a broadband communication channel. The reason for this interest is the rapid increase in bandwidth requirements for communication networks due to the emergence of new broadband services. These services include business services (video conferencing, remote learning, telemedicine) and entertainment services (video on demand, digital broadcasting, HDTV, on-line games, etc.). Currently used technologies cannot provide a cost-effective solution to meet growing needs, so innovative technologies are being used.

One of them is FTTx (Fiber To The ... - “fiber to ...”) - a technology for organizing access networks with bringing optical fiber to a certain point. Despite the fact that FTTx is not a new technology, it is becoming widespread right now.

There are several options for implementing FTTx, of which we can highlight: - Fiber To The Home (bringing fiber to the apartment); - Fiber To The Building (bringing fiber to the building).

In this course project we will implement the presented methods.

1.2 Selection and justification of broadband access technology

The term "broadband" is used to refer to a constant, high-speed Internet connection. However, broadband access is not only a high speed of information exchange, but also a special way of using the World Wide Web. A broadband user has the opportunity at any second to receive or send a large amount of any information, which may include color images, audio and video clips, animation, television content and much more. Broadband access provides the user with the most advanced services, regardless of the point of connection. The owner of broadband access has more opportunities to use multimedia services and provide information for his business. This is file sharing, video conferencing, games; security system services; telephone and banking services, etc. All this has become available thanks to modern broadband access networks (BBA).

Broadband access also contributes to the emergence of new areas of human activity and enriches existing ones. It stimulates economic growth and opens up new investment and employment opportunities.

1.3 Methods for constructing FTTX

FTTX

FTTx technology (English Fiber to the x - optical fiber to point X), the name of which comes from the capital letters of the English expression Fiber-to-the-build/home, which means “optics to every home.” This term is applied to any computer network in which a fiber optic cable reaches from a communication node to a specific location (point X). The wide bandwidth of FTTx systems opens up new opportunities to provide subscribers with more new services.

FTTB

The topology of this network largely replicates a hybrid fiber-coaxial network and also consists of a data transmission node, a backbone fiber-optic communication line (FOCL) and a distribution network. The only difference between FTTB is the replacement of optical GVKS nodes with “second-level nodes” (amplifier points) and the distribution network cables from coaxial cable to optical. The headend and home distribution network do not require changes when upgrading, and the backbone may only require an increase in the number of optical fibers. Based on the above, in FTTB networks the amount of installed optical fiber and installed optical receivers is increasing.

When using the FTTB option, optical fiber is brought into the house, usually in the basement or attic (which is more cost-effective) and connected to an ONU (Optical Network Unit). On the telecom operator's side, an OLT (Optical Line Terminal) optical line terminal is installed. The OLT is the primary device and determines the parameters of traffic exchange (for example, time intervals for signal reception/transmission) with ONU subscriber devices (or ONT, in the case of FTTH).

Further distribution of the network throughout the house occurs via twisted pair cable.

This approach is advisable to use in the case of network deployment in apartment buildings and middle-class business centers. Russian telecom operators are currently deploying FTTB networks only in large cities, but in the future this technology will be used everywhere. With FTTB there is no need to lay expensive optical cable with a large number of fibers, as with FTTH.

FTTH

FTTH - (English Fiber to the Home - optical fiber to the apartment). Considering that Russian subscribers live mainly in apartment buildings, FTTH means, unlike FTTB, bringing optical fiber to the subscriber’s apartment.

There are two types of FTTH network organization: Ethernet-based and PON-based.

Ethernet-based architectures

The need for speed to market and lower cost to subscribers has led to the emergence of network architectures based on Ethernet switching. Ethernet data transmission and Ethernet switching began to generate revenue in the enterprise networking market and led to lower prices, the emergence of complete products and faster

development of new products. At the heart of the first European FTTH Ethernet projects

was an architecture in which switches located on the ground floors of apartment buildings were connected into a ring using Gigabit Ethernet technology. This structure provided excellent resistance to various types of cable damage and was very cost-effective, but its disadvantages included the division of bandwidth within each access ring (1 Gbit/s), which in the long term gave a relatively small throughput and also caused scaling difficulties architecture.

Then the Ethernet star architecture became widespread. This architecture requires dedicated fiber optic lines (usually single-mode, single-fiber 100BX or 1000BX Ethernet data lines) from each end device to a point of presence (POP), where they are connected to a switch. Terminal devices can be located in individual residential buildings, apartments or apartment buildings, on the ground floors of which switches are located, bringing lines to all apartments using appropriate transmission technology.

Ethernet FTTH architecture with Star topology:

PON-based architectures

When using a PON-based architecture to deploy FTTH networks, the fiber optic line is distributed to subscribers using passive optical splitters with fan-out ratios of up to 1:64 or even 1:128. PON-based FTTH architecture typically supports the Ethernet protocol. In some cases, an additional downstream wavelength is used, allowing traditional analogue and digital television services to be provided to users without the need for IP-enabled set-top boxes.

The figure below shows a typical PON that uses various optical network terminations (ONTs) or optical network units (ONUs). ONTs are intended for use by an individual end user. ONUs are typically located in basements or basements and are shared among a group of users. Voice services, as well as data and video services, are transmitted from the ONU or ONT to the subscriber via cables laid at the subscriber's premises.

Passive Optical Network (PON) Architecture:

There are currently three different PON network standards, which are shown in the table. Bandwidth parameters indicate the combined downstream and upstream data rates. This data rate is divided between 16, 32, 64 or 128 subscribers, depending on the deployment plan.

Table Types of PON

BPON architecture is a traditional technology that is currently still used by some service providers in the US, but is quickly being replaced by other architectures. While EPON was designed to reduce cost by using Gigabit Ethernet technology, GPON architecture was designed to provide higher downstream data rates, reduce overhead, and accommodate ATM and TDM traffic. Despite the added support for older protocols, this feature is still rarely used in practice. Instead, the GPON architecture is used as an Ethernet transport platform.

1.4 Communication scheme for FTTX technology

General plan for the construction of fiber optic lines of the course project

FTTB technology organization diagram

FTTH technology organization diagram

2. Selection and justification of the type of optical fiber and optical cable design

2.1 Selecting the type of optical fiber

To implement FTTB technology, you will need the following type of optical fiber and twisted pair G.652 - undispersion-shifted single-mode stepped fiber serves as a fundamental component of an optical telecommunications system and is classified by the G.652 standard. The most common type of fiber, optimized for signal transmission at a wavelength of 1310 nm. The upper limit of L-band wavelength is 1625 nm. Requirements for macrobending - mandrel radius 30 mm.

Parameters of OM rec. G.652

Characteristic
Wavelength, nm
Mode spot diameter, µm
Shell diameter, µm
Diameter of protective coating, microns
	0.6 maximum	0.6 maximum	0.6 maximum	0.6 maximum
Shell flattening	1.0% Maximum	1.0% maximum	1.0% maximum	1.0% maximum
	1260 Maximum	1260 maximum	1260 maximum	1260 maximum
Macrobending loss, dB	0.1 maximum at 1550 nm	0.1 maximum at 1550 nm	0.1 maximum at 1550 nm	0.1 maximum at 1550 nm
Test voltage, GPa	0.69 minimum	0.69 minimum	0.69 minimum	0.69 minimum
Zero dispersion wavelength, nm	from 1300 to 1324	from 1300 to 1324	from 1300 to 1324	from 1300 to 1324
Chromatic dispersion coefficient, ps/nm*km, no more, in the wavelength range: 1285-1330 1525-1575
Sign of dispersion



PMD coefficient, ps/√km

According to the parameters indicated in this table, optical fiber type G.652.A is suitable for us.

Twisted pair CAT6a is a communication cable consisting of one or more pairs of insulated conductors, twisted together (with a small number of turns per unit length), covered with a plastic sheath. Twisting of insulated conductors is carried out to increase the connection between the conductors of one pair (electromagnetic interference equally affects both wires of the pair) and the subsequent reduction of electromagnetic interference from external sources, as well as mutual interference when transmitting differential signals.

To reduce the coupling of individual cable pairs (periodic bringing together of conductors of different pairs) in UTP cables of category 5 and higher, the wires of the pairs are twisted with different pitches. Twisted pair is one of the components of modern structured cabling systems<#"599313.files/image009.gif">

Rice. "Twisted pair CAT6a"

optical technology twisted pair

To implement FTTH technology, optical fibers of the type G.652.A and G.657..657 are required - single-mode optical fiber is characterized by a low level of bending losses, is intended primarily for FTTH networks of multi-apartment buildings, and its advantages are especially obvious in limited space. You can work with G.657 standard fiber almost as if you were working with a copper cable.

Parameters of OM rec. G.657

Characteristic
Wavelength, nm
Mode spot diameter, µm
Shell diameter, µm
Core eccentricity, µm
Shell ellipticity
Cable cutoff wavelength, nm
Macrobending losses, dB: radius, mm number of turns max. at 1550 nm max. at 1625 nm
Test voltage, GPa
Chromatic dispersion coefficient, ps/nm*km, 1285-1330 nm 1525-1575 nm
Attenuation coefficient, dB/km; at wavelength, nm


PMD coefficient, ps/km

2.2 Selecting an optical cable design

To implement our project we will need the following types of optical cables:

OKLSt

Application: optical communication cables are intended for installation in cable ducts, special pipes, collectors, tunnels, on bridges and overpasses, as well as in light soils and in places infested with rodents.

· Use of optical fibers in accordance with Recommendations G.651, G.652, G.655

· Use of dry water blocking materials (“dry” core design).

· Manufacture of the shell from flame retardant materials, halogen-free, with low smoke emission (OKLSt-N brand).

· Manufacture of a cable with an internal aluminum-polyethylene sheath for increased moisture resistance (AlPe).

Description of design:

Cables type OKLST (with one PE sheath up to 192 RH) for laying in cable ducts

2. Central power element (CSE), a dielectric fiberglass rod (or steel cable in a PE sheath), around which optical modules are twisted.

Cordels (if necessary) - solid PE rods for structural stability.

Armor in the form of a steel corrugated tape with a water blocking tape underneath.

The outer shell is made of low or high density PE composition.

Advantages:

· compact design;

· minimum weight;

· excellent mechanical properties;

· resistance to rodents;

· long service life;

· use of materials from the best foreign and domestic manufacturers;

· minimum coefficient of friction.

OKLZht

Application: intended for hanging on utility poles; suspensions on supports of railway contact networks and overhead communication lines; air laying on the supports of the city energy sector; gaskets on trays and trestles.

· Use of optical fibers in accordance with Recommendations G.651, G.652, G.655;

· Use of a hydrophobic compound to fill the voids of the twist along the entire length;

· Manufacturing of the outer shell from flame retardant materials;

· Use of tearing cords;

· Manufacturing of cable with two PE sheaths;

· Manufacturing of cables with up to 192 fibers;

· Calculation of the design and parameters of the cable according to the requirements of a specific project, depending on the values of span lengths, sag arms and operating conditions;

Description of design:

Cables type OKLZH-(T) (from 2 to 144 OV) for aerial installation (classic design, in accordance with TT FSK)

1. Optical fibers are loosely laid in polymer tubes (optical modules) filled with thixotropic gel along the entire length.

2. Central power element (CSE) in the form of a fiberglass rod around which optical modules (modules and cords) are twisted.

Cordel - solid PE rods - for structural stability.

Waist insulation in the form of Mylar tape, applied over the twist.

Hydrophobic gel that fills the voids of the twist along the entire length.

The inner shell is made of low or high density PE composition.

Power elements in the form of a layer of aramid threads.

The outer shell is made of high density PE composition.

Advantages:

· minimum weight and diameter;

· high mechanical properties;

· optimal rigidity and low coefficient of friction of the shell (for blowing into special pipes);

· low gasket temperature;

· large temperature range during operation;

· selection of the optimal design for specific operating conditions;

· ease of installation and installation;

· long service life.

2.3 Selection and justification of cross-connect equipment

Block diagram of the FTTB aggregation node configuration

Optical cross-country unit KRS-48

Description

The KRS-48 model belongs to a series of standard rack-mount switching and distribution devices of the 2U form factor and provides switching of up to 48 optical ports FC, ST, SC, MT-RJ, E-2000 and up to 72 LC ports.

The optical adapters are mounted on 4 replaceable strips, which are attached to the front panel of the case using two latches.

Patchcord organizer

Description

They are designed to allow cables to be routed from inside the cabinet, such as from the back of patch panels, to connect to the front of network equipment. Compact, only 1U high, the organizer has a special hole in the center, protected by brushes that prevent dust and other contaminants from getting inside the cabinet. Two holders are used for cable management. The holders have slits at the front, allowing cables to be easily stored and removed.

Pigtail SM

Description

The installation optical cord (pigtail) SM is used for terminating the main optical cable when wiring in distribution cross-connect equipment.

It is a piece of fiber optic cable terminated on one side. Pigtails are used for quick termination of fiber optic cables when installing communication networks by attaching the pigtail to the cable using welding or mechanical connectors. Essentially, a pigtail is an optical cord (patch cord) without a second connector, so requirements for pigtails are similar to those for patch cords. Accordingly, much attention is paid to the quality of the pigtail, forward and reverse losses, asymmetrical position of the fiber in the connector ferrule, and mechanical strength.

Pigtails are used when installing passive distribution devices, such as optical cross-connects.

Optical sockets

Description

Optical sockets - designed for connecting optical cords with FC/PC connectors. Provides high-quality alignment of connectors thanks to a high-precision centralizer, and the clamps provided by the design ensure reliable fixation. The optical pass-through adapter is protected from contamination and dust by plastic plugs.

Patchcord SM FC-LC duplex

Description

A patch cord is an optical cable that ends on both sides with connectors of various types. It is used to connect optical telecommunications equipment to the optical cross-connect.

Typology of patch cords:

Based on the type of cable used in the production, patch cords are divided into: single-mode “SM” (singl-mode) or multi-mode “MM” (multi-mode).

Based on the type of cable used in cable production, patch cords are divided into: duplex “DPX” (duplex) or simplex “SPX” (simplex).

In addition, they differ in the type of connectors - “FC”, “LC”, “SC”, “ST”, “MT-RJ”, they can be connecting (identical connectors on both sides) or transition (different connectors on different sides ).

Patchcord SM LC-LC duplex

Description

Optical connecting cords with LC connectors. Patch cords are made from 9/125 µm single-mode fiber, 50/125 µm multi-mode fiber or 62.5/125 µm fiber. The cable is covered with a protective sheath of yellow, orange, white or blue, depending on the type of cable.

Switch 100Base-FX(24 ports)+10GBase-L(2 ports)

Description

Switch - a device designed to connect several nodes of a computer network within one or more network segments<#"599313.files/image022.gif">

SFP optical module

Description

SFP modules are designed for installation in a router or switch slot and provide its connection to the network using the required interface. SFP converters support hot-swap mode. Various modules are available that allow you to connect the necessary equipment to various transmission media: multimode optical fiber, single-mode optical fiber, twisted pair. The GLC-T 1000Base-LX module provides data transmission over Category 5 twisted pair cable over a distance of up to 100 meters.

XFP optical module

Description

This module supports digital diagnostic technology, which allows real-time monitoring of device operating parameters, such as: operating temperature, laser current deviation, emitted optical power, received optical power, supply voltage.

An alarm system is supported when parameters go beyond the established tolerances.

Block diagram of the FTTB access node configuration

Pigtail FC/PC SM (0.9) 1.5m

Optical mounting cord

Connector type: FC

Fiber Type: Singlemode

Cord type: Simplex

Buffer: 0.9/3mm.

Length: 1.5 meter.

Optical socket FC/PC/SM

Designed for connecting optical cords with FC type connectors. Provides high-quality alignment of connectors thanks to a high-precision centralizer, and the clamps provided by the design ensure reliable fixation. The optical pass-through adapter is protected from contamination and dust by plastic plugs.

Square socket - type S, fixed in a cross with screws. Connector type: FC

Case material: metal

Body color: silver, yellow or red caps

Centralizer material: zirconium ceramic

Polishing of connectors: PC/UPC/SPC

Fiber Type: SingleMode

Socket type: simplex

Patchcord SM FS-LS duplex

The thickness of the cord is usually 2 or 3 mm, length - 1, 2, 3 or more meters. Optical patch cords can consist of single-mode fibers SM (Single Mode) 9/125 (understood as the diameters of the light-conducting core/cladding in microns) or multimode fibers MM (Multi Mode) 50(62.5)/125 (respectively, meaning the diameters of the optical fiber and its isolation). Patch cords can consist of one fiber (Simplex) or two (Duplex).

Mechanical characteristics:

Cable color yellow

Number of starts 1000

Vibration 1...200Hz with acceleration 4g

Impact 40g pulse duration 18ms

Climatic characteristics:

Temperature range - 40 °C to + 80 °C

Atmospheric pressure 26kPa

Relative humidity 100% at +25°C

Tip end geometry

Radius of curvature, mm 10...25

Apex displacement, µm<50

Fiber end position, nm. +50/-50...-125

Optical characteristics

Direct loss, dB max. 0.25 typ. 0.1

Return loss, dB min. -50 typ. -55

Cost of each additional meter: 36 rubles.

Optical module sfp 1000 base-LX

Optical interface with SC connector;

Single fiber WDM transceiver;

Operating wavelengths 1310nm, 1550nm, single-mode fiber;

Signal transmission range 3 km;

Data transfer rate 1.25 Gbps;

Possibility of execution with an extended temperature range (-40..+85);

Complies with RoHS directives;

Electronic electricity meter Mercury-200

Electricity metering and metering in the residential, small motor and industrial sectors

Accuracy class: 2.0

Rated-maximum current, A: 5-50

Nominal frequency 50 Hz

The total and active power consumed by the voltage circuit is 10VA and 2.0W, respectively

The total power consumed by the current circuit is no more than 2.5 VA

Operating temperature range, 0С: from -20 to +55

Calibration interval: 8 or 16 years (see modifications)

Average service life: at least 30 years

Number of tariff zones: 1-4

Multi-tariff meters have a serial built-in CAN interface that provides information exchange with a computer

Possibility of mounting both traditionally and on a DIN rail

Introductory power supply circuit breaker

Automatic machines (circuit breakers) are designed to protect electrical circuits - your electrical wiring from overloads and short circuits. This is a good alternative to today's outdated plugs, automatic plugs, which lose both in safety and reliability, as well as in quality and durability. Modular machines are used in everyday life. Externally, they are very neat, taking up little space in the shield due to their compactness. Very convenient and easy to install: to install them you just need to snap them onto the DIN rail. If necessary, they can be easily replaced. The correct selection of machines is very important. To do this, calculate the total power consumption of your electrical appliances (you can use their passports), expressed in watts (W) and divide it by the voltage of your network ~ 220 V. However, the load on the network is usually reactive in nature.

Standard terminal block AVK 2.5

General information about the product:

Insulating material PA 66

Ignition class acc. up to UL 94 V2

Width 5 mm

Length 44.2 mm

Height (MR 35) 44.5 mm / CE Technical data

Rated voltage 750 V

Rated current 24 A

Section 2.5 mm2

Standard EN 60947-7-1 Technical data

Rated voltage 750 V

Rated current 24 A

Section 2.5 mm2

VDE standard IEC 60947-7-1/ CSA Technical data

Rated voltage 600 V ~

Rated current 20 A Cross section 26-12 mm2 Technical data

Rated voltage 630 V

Rated current 21 A 2

Section 2.5 mm2

Connectable wires

Minimum single-core cross-section 0.5 mm2

Maximum single-core cross-section 4 mm

Minimum stranded cross-section 1.5 mm2

Maximum stranded cross-section 2.5 mm2Section 26-12

Vidali connection type

Insulation stripping length 10 mm

Tightening torque 0.4 Nm

Double conversion uninterruptible power supply (Ippon Innova RT 1000)

Phase input voltage

output power 1000 VA / 900 W

output connectors: 8 (battery powered - 8)

rack-mountable

interfaces: USB, RS-232

Output waveform: sine wave

Horizontal wall patch panel 24*RJ-45, UTP, Cat.5e

The patch panel for wall mounting has 24 ports and a design that allows installation and cutting from the front side, after first removing the decorative and protective cover.

Bandwidth, MHz: 100

Number of ports: 24

Version: Not shielded

Jack type: RJ45/8P8C

Contact coating material in connector: Gold, 50 microinches

IDC contact type: 110

IDC contact coating material: C5191

Permissible diameter of the embedded core, AWG (mm): 24-26 (0.511-0.404)

Wiring diagram: T568A/B

PCB material: FR 94-V0

Labeling: All ports are numbered on the front. There are additional areas for port marking.

Supporting structure material: Steel 1.52mm

Compliance with standards: ISO/IEC 11801-2, EN 50173-2, TIA/EIA 568-B.2

Supported applications: 10Base-T, 100Base-TX, 1000Base-T

Temperature ranges, C: Storage from -40 to +70

Operation: from 0 to +70

Mounting: Wall

Dimensions HxWxD, mm: 69.85x287.02x25.65

KRS-24, cross optical 19 1U 24 ports

KRS-24, rack-mount optical crossover with 24 ports - designed for terminating an optical cable, protecting the welding site from external influences and mounting in a 19" rack. The crossover is equipped with three replaceable strips: 3 strips for 8 ports of any type to choose from: SC, FC, ST , LC, etc. Depending on the type of installed replacement bar, the name of the cross also changes.

Main characteristics: Form factor: 1U

Case material: metal

Overall dimensions: 405x230x44 mm.

Weight: 2.1 kg.

Add. information: there are 4 options for cable entry, from different sides of the optical cross-connect

Ethernet switch 10/100 base T embedded

Allows you to create computer networks (including computers, printers, servers) without patch panels. On peripheral equipment, it is necessary to use 10/100 base T Ethernet network cards for data exchange at a speed of 10/100 Mbit/s. It is possible to expand the existing network by replacing the RJ 45 socket. Voltage indicator lamp on the front panel. Convenient and functionally reliable access to the Reset function 6 RJ 45 ports Cable connection to 1 side RJ 45 connector Tool-free connection socket, also used for communication tests Installed in a 3-gang Batibox deep. 50 mm (recommended).

Block diagram of the PON P2MP aggregation node configuration

Optical module xpf 10GBASE-LR

Characteristics:

Standard: IEEE 802.3ae 10GBASE-LR 10Gigabit Ethernet

Optical receiver sensitivity -12.6dBm (max)

Transceiver type: XFP (Small Form Factor Pluggable)

Connector: Duplex LC

Data transfer rate: From 9.95 Gbps to 10.7 Gbps

Wavelength: 1310nm

Cable type: Single-mode optical cable 9/125µm

Maximum cable length: 10 km

Physical parameters

Supply voltage

+3.3V and +5.0V supported

Working temperature

-5o to 70o C

Storage temperature

-40o to 85o C

Humidity

0% to 85% relative humidity

EMI Certificates

FCC Class B

Patchcord SM SC-SC/APC simplex

The SC-SC APC 9/125 single-mode simplex optical cord is used for switching between optical cross-connects, connecting optical equipment, connecting optical cross-connects. They also have alternative names - optical patch cord SC-SC and optical connecting cord SC-SC. Pay attention to the type of optical cable, the type of optical connectors on both sides and the type of ferrule grinding in order to avoid installation problems.

End diameter

Fiber type

Singlemode, SingleMode

Connector type SC

Polishing type

Connector color

Secondary Buffer Color

Tip material

zirconium dioxide

Return Loss

Insertion loss

≤ 0.3 dB

Pigtail sm sc/PC

Optical mounting cord SC PC 62.5/125 is used for terminating optical communication lines in optical cross-connections. The cord needs to be cut in half to get 2 pigtails. The price is for 1 pigtail. Pay attention to the type of optical cable, type of optical connector and type of ferrule grinding in order to avoid installation problems.

Optical socket SC/PC SM

The SC/PC SM simplex optical socket is a device that serves as a connecting element when using a fiber optic cable. Designed to operate in single-mode mode.

Specifications:

Designed for 500 starts.

SC connector type.

Possible direct losses are no more than 0.2 dB.

Operating temperature range from -40o C to +75o C

Block diagram of the PON P2MP access node configuration

Optical splitter

Purpose

The main purpose of the planar PLC splitter is use in PON networks. At any site: at a station, in a coupling, when entering a house, the optical signal is divided between several users into several fibers using a passive device that does not require maintenance - a splitter.

Possibilities

There are the following options for the luminous flux division coefficient using splitters: 1x2, 1x4, 1x8, 1x16, 1x32, 1x64.

Various manufacturing options for splitters allow their use in PON networks of any architecture, regardless of the data transmission technology used by the operator.

The minimum dimensions of the splitter (4x4x40 mm), as well as the use of splitters already terminated with an SC connector with a pigtail of various lengths, provide a flexible approach to network installation.

The splitter can be integrated into an optical distribution box, coupling, street and access cabinets, floor boxes, or directly into a subscriber access device.

Specifications

Splitters support all types of FTTH network architectures:

· BPON, GPON, GE-PON, P2P;

· data transfer.

Configuration

· unfinished for welding (for example, in couplings);

· terminated with connectors of the following types: FC, SC, LC;

· connector polishing type: SPC, UPC, APC.

Execution

· in a compact steel case with fiber outputs in a tape design;

· in a compact steel case with fiber outputs in the shell of 900 microns;

· in an aluminum/plastic case with fiber outputs in a patchcord sheath of 2-3 mm;

· for installation in 19"" frame, ODF.

Specification

Wavelength.............................1260…1360 Nm, 1450…1625 Nm

Maximum input signal...............17 dBm, 1550 Nm

Operating temperatures......-40°C…+85°C

Rel. Humidity........................5% … 85%

Dimensions (HxWxD, mm):

x4, 1x8................................4 x 4 x 40 mm

x 16........................................5 x 4 x 40 mm

x 32........................................7 x 4 x 50 mm

In a boxed version.............10 x 80 x 100 mm

Available in 19" ......................44 x 300 x 482.6 mm

Optical characteristics	Specification
Optical splitter configuration
Insertion loss, dB*
Permissible unevenness of optical power division between output ports, dB*
Allowable changes in optical power losses during transmission between the input and each of the output ports, due to changes in polarization, dB*
Return loss, dB
Directivity, dB
Operating wavelength
Operating temperature range, °C

Optical cross connectors KRS-8, KRS-16 and KRS-24 for rack mounting

Rack-mount optical cross connects are convenient patch panels for connecting and distributing linear optical cable fibers using optical pigtails and patch cords. Made of lightweight aluminum alloy with anti-corrosion coating, or steel with protection degree IP-55. Cassettes for laying welding spots allow the use of heat-shrinkable KDZS tubes with a length of 60 mm or 40 mm. FC, SC or ST type adapters are installed in special sockets.

Certificate of Conformity of the State Committee for Communications of the Russian Federation No. OS-1-OK-125

Subscriber optical cross

The SKRU rack-mount cross distribution device is designed for termination, distribution and switching of optical cables, connection of optical fibers to the equipment of optical transmission systems, as well as for monitoring the characteristics of the optical cable during operation.

Dimensions: 485x212x44 mm

Weight: 2.0 kg

Features: Metal structure with a thickness of 0.8-1.0 mm provides the necessary rigidity of the product and is installed in mounting racks (cabinets) of a 19” design

The oblong cable entry is located on the rear side of the housing

The KU-01 splice plate provides a bending radius of at least 30 mm, which avoids additional losses during the operation of fiber-optic lines.

Equipment:

Splice plate KU-01

Cover for splice plate KU-01

Splice plate fastener

Marker table

Nylon zip ties

TsSE fasteners

M5 screws (for fastening the TsSE to the body)

Adapter strips

Blank strips

Self-adhesive pads with cable clamps

Metal clamp for attaching the cable to the housing

Individual corrugated cardboard packaging

3. Selection and justification of equipment

3.1 Optical line terminal equipment

The optical line terminal (OLT) is designed to organize broadband multiservice multiple access over an optical fiber with a tree structure in accordance with the G.983.X standard using PON technology.

The PON G.983 standard covers the passive component of the network and active devices, regulates the interaction protocols between the central OLT node and ONT subscriber nodes, the parameters of optical transceiver interfaces (signal power, wavelengths) for OLT and ONT, determines the permissible topologies and the length of the P0N network . P0N technology involves the use of the C-band (1530-1565 nm) for transmitting DWDM signals.

In accordance with the G.983.1 standard, one fiber-optic segment of the PON network can cover up to 32 subscriber nodes within a radius of up to 20 km.

Each subscriber node is designed for an ordinary residential building or office building and, in turn, can cover hundreds of subscribers, providing service interfaces 10/100Base-TX, E1/E2/EZ/E4, digital video, ATM, STM-1/4.

The central node may have ATM, SDH (STM-1/4/16), Gigabit Ethernet network interfaces for connecting to backbone networks.

Functional features of OLT application:

· Optical fiber is becoming the best medium for building backbone and small-diameter access networks.

· Passive branch nodes can significantly increase network reliability by eliminating intermediate active elements between the central office and the subscriber node.

· With the most advanced concept of FTTH (fiber to the home), each subscriber becomes a terminal.

· Thanks to the gigantic fiber capacity, the optimal solution is achieved when one fiber coming from a central node or otherwise POP (Point-Of-Presence) is branched to many subscribers. This makes the construction of a fiber-optic cable system economical and reduces subsequent costs of maintaining it.

· Solutions based on PON and DWDM technologies best meet these requirements.

· Significant reduction in the cost of using PON technology in the basic version of two wavelengths (1550 nm, 1310 nm).

· Optical fiber bandwidth is used efficiently.

· The network is built with passive fiber branching.

· PON - Multiservice network.

· Dynamic bandwidth allocation.

· Natural evolution to DWDM network.

· Possibility of reserving both all and individual subscribers,

· Transformation of the "last mile" concept into the "first mile" concept.

3.2 ONU equipment

Device versatility

One of the important distinguishing features of the DIR-100 device is its versatility. By purchasing the DIR-100, the user can decide for himself which device to use it as: a broadband router, a Triple Play router or a VLAN switch. To receive a new device, simply download the necessary software from the D-Link FTP server. However, the device hardware remains unchanged. Here is a description of the functionality of the DIR-100 as a Triple Play router.

Triple Play Services

The popularity and availability of Triple Play services is growing day by day. The user simply needs to connect the Triple Play router and order the corresponding service from the provider. The Triple Play DIR-100 router, recommended for use in provider networks, allows users to access the Internet, watch IPTV broadcasts and use VoiceOverIP services with guaranteed transmission speeds. Thus, using one WAN connection, voice, video and Internet traffic are simultaneously transmitted (Triple Play).

The principle of operation of the device is quite simple. Its two ports support NAT and firewall functions. These ports are intended for connecting personal computers and organizing access to the Internet. The other two ports do not support routing functions - these ports are connected to the WAN port in transparent bridge mode. It is possible to connect to these two ports, for example, an IP telephone or equipment necessary for the implementation of IP television services (IPSTB).

VLAN and queue prioritization support

Support for virtual VLANs (802.1Q and port-based) is especially important for this device. Because it is this function that allows each type of traffic to be transmitted over its own virtual network.

The device also supports 802.1p queue prioritization to ensure proper quality of service, allowing users to use latency-sensitive applications such as audio/video streaming and VoIP over the network.

Safety

The ports of the Triple Play DIR-100 router, designed for connecting personal computers, are equipped with security functions. Thus, they have a built-in firewall to protect computers on the network from virus and DOS attacks.

HTV-1000 is a reliable and time-tested set-top box that allows IP TV service operators to quickly and inexpensively deploy a television broadcast network of any scale.

supports major media protocols

DOLBY DIGITAL digital surround sound support

HDTV support

ability to record TV programs

low cost of organizing Internet television networks on a city scale

high price/quality ratio

The device can be connected to any television signal receiver.

Features of the TV set-top box

Watching HD video and TV content

Viewing multicast streams (TV channels) according to the list

Generating a list of TV channels manually

TV channel preview window

Image format conversion

Playback of video and audio data of various formats: MPEG-TS, MPEG-PS, avi, mkv, mov, mp4, wmv, ac3, mp3, wmv

Decoding of video streams of the following standards: MPEG2, MPEG4P2, h264,VC-1, WMV9

Decoding audio streams of the following standards: mpeg2-audio, mp3, AC-3

Playing media data located on UPnP servers

Playing media data from USB flash memory, disks

Possibility of connecting a USB keyboard, USB mouse

Support for SMB and NFS file systems

Support for WI-FI usb adapters

Built-in YouTube player

Built-in WEB browser

Built-in list of Radio Stations

Access to Picassa

Built-in game programs

Controlling the volume level and muting the set-top box from the remote control

Low power consumption

For IP TV operators and video content providers

Logo installation

Installing an operator key, digital signature

Installing the set-top box control key

Remote software update

Open source software makes it possible to adapt your own control and monitoring systems

Adding your own commands

Remote control of the front panel indicator

Remote restart of the set-top box with changing the boot mode

Playing content from the operator's UpnP media server

Java Script capabilities - to control the IPTV set-top box, play various types of content and configure the set-top box's behavior model

Technical characteristics of the set-top box

Video modes

HD 1080i720p/i576p/ito 1920 x 1080 x 32 bitTV standard 4:3 or 16:9

Video codecs/2 [email protected] HP@level 4.1 up to 30 Mbit/s

MPEG4 part 2 (ASP) DivX4, DivX5, XviD

Audio codecslayer I/IIlayer IIlayer III (mp3)Digitalsubtitlesmedia protocols: RTSP, RTP, UDP, IGMPon-Chip (SoC)DDR 128MbFlash 1Mb, Flash 128Mb

Software shutdown, 5 V; 1.5 Aout: RCA, S-Video, SCART, HDMI, Component RGB or (Y Pr Pb): S/PDIF (Dolby AC-3 multi-channel), LR RCA2.0

control panel RC-510/100Base-T Auto MDI/MDIX RJ-45

operating temperature range, 10°C- 40°C

storage temperature range, 0°C-50°C

humidity 40%~60%

supply voltage 100-240 V,50/60 Hz, 7W

dimensions 300 mm x 237 mm x 64 mm

Base operating system linux2.6.16agent: WebKit

built-in media portal with IPTV functionality

HTTP 1.1, HTML 4.01 XHTML 1.0/1.11, 2, 3, CSS 1, 2, 31.0, XSLT 1.0, XPath 1.02.01.1ECMA-262, revision 5JavaScript API

latest firmware release 0.2.03

MiddleWare is supplied separately for the broadcast operator node

support for SAMBA and NFS protocols

It is also possible to transfer data not via cable, but via Wi-Fi

D-Link DVG-2001S IP telephony gateway, which is a universal solution with which you can integrate Internet telephony into your home or office telephone network. Many will be surprised: why do you need an IP phone at home? Until recently, this would indeed have seemed like a useless undertaking, but IP telephony is increasingly crowding out its traditional ancestor. So, for example, when connecting to an operator, a SIPNET user gets the opportunity to:

· significantly save on international and long-distance calls

· communicate free of charge with other subscribers of the SIPNET network

· call from anywhere to Moscow and St. Petersburg for free

· personalize the cost and quality of calls in any direction

· order a connection between two subscribers anywhere in the world

Any Internet user with broadband access with a speed of 64 Kb/sec or higher can connect to SIPNET. To do this, just install one of the standard softphones on your computer or buy a SIP phone or SIP gateway. We will talk about one of them in this article. S opens the D-Link line of VoIP gateways, it is extremely easy to configure and operate, reliable and compact.

Device Specification:

Ports: 1 FXS port, 1 Ethernet 10/100 Mbps port

· supported protocols: SIP

· compression: G.711/G.723/G.729AB;

echo removal method: G.168

· stream: 6-64 kbps (depending on codec)

· support for DHCP, PPPoE;

NAT traversal support

· Possibility to update firmware

The device is equipped with one FXS port for connecting an analog telephone and one LAN port (Fast Ethernet) for connecting to a home or office network. The gateway cannot boast of a built-in router or switch. The LAN port connects to a switch or ADSL modem/router, and any telephone device can be connected to the telephone jack. You can choose any device you like: a DECT handset, a telephone with an answering machine, etc. The ability to choose from a huge variety of phones is one of the advantages of IP gateways over IP phones, the range of which is significantly limited.

For IP telephony to work you need software called X-lite

X-lite settings

Download the program<#"599313.files/image041.gif">

A window with current accounts appears:

Select add (Add...)

Fill in the following:

Display name - the name displayed on the phone, for example Vasya

User name - your login for<Домашнего Интернета>, for example for now it will be 7846XXXX

Password - your password in our system.” should be replaced with “your password”

Authorization user name - the same as User name but without 7846

Domain - 88.200.176.4

We leave the remaining bookmarks as default.

The phone is ready to use

After setup, a dialog box will appear asking you to update the program version: A new version of X-Lite is available for downloading. Do you want to download it now?. You must refuse the update by clicking "No".

Click on the arrow (Show menu) and select "About".

Version 3.0 build 29712 Build 41150 works fine. Problems with hearing can be caused by firewalls, antivirus, router, etc.

4. Calculation of optical path parameters

4.1 Calculation of optical power budget for FTTB

Transmission of information with the required quality in the regeneration section of the fiber optic line without optical amplifiers, taking into account losses and dispersion distortions, is ensured by a power reserve (net power budget) equal to the difference between the energy potential of the fiber optic transmission line (covered by attenuation) and the optical power costs for losses and interference suppression and distortion of optical pulses in the line:

[dB], where:

The total value of additional losses consists of additional losses due to the laser’s own noise, due to noise due to the radiation of optical power when transmitting “zero”, due to intersymbol interference noise and, accordingly, is equal to:

Additional losses due to the radiation source’s own noise are calculated using the formula:

[dB]

< RIN<-140 дБм.

Let RIN=-130[dBm]

Additional losses due to noise due to radiation of optical power when transmitting “zero” are determined by the formula:

[dB], where:

[dB]

4.2 Calculation of attenuation in the optical path for FTTB

Here, the component of Rayleigh scattering loss at a wavelength is determined by the relations:

,, Where ,

, Where ;

This is the reference wavelength;

[dB/km]

[µm]=800 [nm]

[dB/km]

4.3 Calculation of energy reserve for FTTB

To characterize the FOCS power budget, the concept of energy potential (overlap attenuation) is introduced, which is defined as the permissible optical losses of the optical path or ECU between normalization points at which the required quality of digital optical signal transmission is ensured. Optical losses are due to attenuation losses and additional power losses due to the influence of reflections, dispersion (chromatic and polarization mode), mode noise and chirp effect.

The energy potential is calculated as the difference between the power level of optical radiation at the transmission and the sensitivity level of the receiver

Values and in Table 1.

[dBm].

4 Calculation of optical power budget for FTTH

[dB], where:

Attenuation of ESC together with station cables (patch cords);

Total value of additional losses, dB.

The maximum attenuation value of the ESC together with station cables (patch cords) is calculated as follows:

[dB], where:

The number of permanent connections of the OB on the ECU.

The number of permanent connections on the ECU is equal to:

Additional losses due to the radiation source’s own noise are calculated using the formula:

[dB]

The value of the source's own noise parameter - RIN usually lies within -120< RIN<-140 дБм.

Let RIN=-130[dBm]

Additional losses due to noise due to radiation of optical power when transmitting “zero” are determined by the formula:

[dB], where:

The ratio of the power of optical radiation from a source when transmitting “zero” to the power of optical radiation when transmitting “one”. As a rule, the value of this value lies in the range of 0.01 0.1.

[dB]

4.5 Calculation of attenuation in the optical path for FTTH

The attenuation coefficient is calculated at the central wavelength of the optical channel. It is first necessary to determine the spectral range in which the central wavelength lies. To calculate the spectral loss characteristics of an optical fiber, we will use well-known approximate formulas. The resulting fiber attenuation coefficient in dBm/km is given by the sum of:

Here, the component of Rayleigh scattering loss at a wavelength is determined by the relations:

,, Where ,

The loss component due to OH- impurities is calculated as follows:

, Where ;

This is the reference wavelength;

[nm], since the central wavelength is closer to 1550 [nm].

Reference wavelength attenuation coefficient:

[dB/km]

[µm]=800 [nm]

[dB/km]

Resulting fiber attenuation coefficient:

Maximum optical fiber attenuation coefficient:

[dB/km]

3 Calculation of energy reserve for FTTH

The energy potential is calculated as the difference between the power level of optical radiation at the transmission and the sensitivity level of the receiver

where W is the energy potential (overlap attenuation), dBm;

Optical radiation power level of the FOSP transmitter, dBm;

Receiver sensitivity level, dBm.

Values and in Table 1.

5. Security system for FTTx technology

5.1 General provisions

Choosing the Right Topology

It is not recommended to use hubs for VoIP infrastructure, which make it easier for attackers to intercept data. In addition, since digitized voice typically travels over the same cable system and through the same network equipment as conventional data, the information flows between them must be properly delineated. This, for example, can be done using the VLAN mechanism (however, you should not rely on them alone). It is advisable to place servers participating in the IP telephony infrastructure in a separate network segment, protected not only by the protection mechanisms built into switches and routers (access control lists, address translation and attack detection), but also with the help of additionally installed tools (firewalls, systems attack detection, authentication systems, etc.).

Physical Security

It is advisable to prohibit unauthorized user access to network equipment, including switches, and, if possible, place all non-subscriber equipment in specially equipped server rooms. This will prevent unauthorized connection of an attacker's computer. In addition, you should regularly check for unauthorized devices connected to the network that can be “embedded” directly into the network cable. Such devices can be identified in different ways, for example, using scanners (InternetScanner, Nessus), which remotely recognize the presence of “foreign” devices on the network.

Access control

Another fairly simple way to protect your VoIP infrastructure is to control MAC addresses. Do not allow IP phones with unknown MAC addresses to access gateways and other elements of the IP network that transmit voice data. This will prevent unauthorized connection of “foreign” IP phones that can listen to your conversations or carry out telephone communications at your expense. Of course, the MAC address can be faked, but you still shouldn’t neglect such a simple protective measure, which can be implemented without any problems on most modern switches and even hubs. Nodes (mainly gateways, dispatchers and monitors) must be configured to block all unauthorized attempts to access them. To do this, you can use both capabilities built into operating systems and products from third parties. And since we work in Russia, we should use products certified by the State Technical Commission of Russia, especially since there are a lot of such products.

Virtual Local Area Network (VLAN) technology provides a secure division of a physical network into multiple isolated segments that operate independently of each other. In IP telephony, this technology is used to separate voice transmission from regular data transmission (files, email messages, etc.). Dispatchers, gateways, and IP phones are placed on a dedicated VLAN for voice. As I noted above, VLAN makes life much more difficult for attackers, but does not eliminate all problems with eavesdropping on conversations. There are techniques that allow attackers to intercept data even in a switched environment.

Encryption

Encryption must be used not only between gateways, but also between the IP phone and the gateway. This will protect the entire path that voice data takes from one end to the other. Privacy is not only an integral part of the H.323 standard, but is also implemented in the equipment of some manufacturers. However, this mechanism is almost never used. Why? Because the quality of data transmission is a top priority, and continuous encryption/decryption of a voice data stream takes time and often introduces unacceptable delays into the process of transmitting and receiving traffic (a delay of 200-250 ms can significantly reduce the quality of conversations). In addition, as mentioned above, the lack of a single standard does not allow all manufacturers to adopt a single encryption algorithm. However, in fairness, it must be said that the difficulties of intercepting voice traffic so far make it possible to turn a blind eye to its encryption. But you still shouldn’t give up encryption completely - you need to secure your negotiations. In addition, you can use selective encryption only for certain fields in VoIP packets.

Firewall

The corporate network is usually protected by firewalls (FWs), which can also be successfully used for VoIP infrastructure. You simply need to add a set of rules that take into account the network topology, the location of installed IP telephony components, etc. Two types of firewalls can be used to protect IP telephony components. The first, corporate, is installed at the exit from the corporate network and protects all its resources at once. The second type is a personal firewall that protects only one specific node, which can host a subscriber point, gateway or Protector manager. In addition, some operating systems (Linux or Windows 2000) have built-in personal firewalls, which can be used to enhance the security of your VoIP infrastructure. Depending on the IP telephony standard used, the use of firewalls can lead to different problems. After subscriber stations have exchanged information about connection parameters using the SIP protocol, all interaction is carried out through dynamically allocated ports with numbers greater than 1023. In this case, the ITU “does not know” in advance which port will be used for the exchange of voice data, and will block such exchanges. Therefore, the firewall must be able to analyze SIP packets in order to determine the ports used for communication and dynamically create or change its rules. A similar requirement applies to other IP telephony protocols. Another problem is related to the fact that not all ITUs are able to competently process not only the header of the IP telephony protocol, but also its data body, since often important information, for example, information about subscriber addresses in the SIP protocol, is located in the data body. A firewall's inability to "get to the bottom of things" can result in voice communications being unable to be exchanged through the firewall or leaving a hole in the firewall that is too large for attackers to exploit.

Authentication

Various IP phones support authentication mechanisms that allow you to use its capabilities only after presenting and verifying a password or personal PIN number that allows the user to access the IP phone. However, it should be noted that this solution is not always convenient for the end user, especially in conditions of daily use of an IP phone. The usual contradiction between security and convenience arises. 1918 and address translation

It is not recommended to use Internet-accessible IP addresses for VoIP; this significantly reduces the overall security level of the infrastructure. Therefore, whenever possible, use addresses specified in RFC 1918 (10.x.x.x, 192.168.x.x, etc.) that are not routable on the Internet. If this is not possible, then you need to use the networkaddress translation (NAT) mechanism on the firewall protecting your corporate network.

Attack detection systems

We have already discussed above some attacks that can disrupt the operation of the VoIP infrastructure. To protect against them, you can use well-proven and well-known attack detection tools in Russia (intrusiondetection system), which not only promptly identify attacks, but also block them, preventing them from harming the resources of the corporate network. Such tools can protect both entire network segments (for example, RealSecureNetworkSensor or Snort) and individual nodes (CiscoSecure IDS HostSensor or RealSecureServerSensor). The versatility and breadth of the topic do not allow us to consider in detail the information security of IP telephony. But the aspects that I was able to cover still show that VoIP is not such a closed and incomprehensible area as it seems at first glance. Attack methods already known from conventional telephony and IP networks can be applied to it. And the relative ease of their implementation puts security in first place along with ensuring the quality of IP telephony service.

2 Security system against vandals (based on Censor)

Security of "passive" FTTH (PON) cabinets

The main feature of broadband networks with PON technology is that a completely passive optical network with a tree topology is created between the central node and remote subscriber nodes. The intermediate nodes of the tree contain passive optical splitters (splitters) that do not require power or maintenance. Splitters, as a rule, are placed in vandal-proof cabinets, which are not of interest to attackers as a subject for theft and profit. However, being installed in the entrances of apartment buildings, they are often subject to acts of vandalism, committed without a specific purpose by “unreliable contingent”. There are also acts of intentional damage to such property by unscrupulous competitors of the operator. Consequently, the issue of ensuring the safety and protection of “passive” cabinets is no less pressing than the same issue in relation to cabinets with active equipment.

At the same time, the FTTH cabinet has neither power supply nor a physical Ethernet port for connecting equipment to the center - that’s why it is “passive”. Providing power entails laying cables, installing an uninterruptible power supply, an electricity meter, etc. Creating an Ethernet port from an optical termination, essentially intended to generate revenue from subscribers, is extremely ineffective economically. Not to mention the fact that with all such organizational and technical measures, the security system will require a separate anti-vandal cabinet, which in cost can exceed all protected cabinets. Consequently, the security principle of installing an independent monitoring device in each cabinet, requiring power and a communication channel, is not suitable here. Yes, this is also impractical, because in such a cabinet there is nothing special to control - only opening. So, does the problem have no solution? As it turns out, there is a solution, and a very successful one! Moreover, for the operators of OJSC Svyazinvest and alternative operators that have their own traditional fixed-line networks, it looks especially elegant! And it was proposed by the Customers themselves - Users of the APK "CENSOR".

It is possible to implement the protection of FTTH (PON) cabinets with the help of the APK "CENSOR" using existing equipment manufactured and supplied to customers today - based on the unique well security system "SOKOL" of its own design and production of JSC NPC "Computer Technologies".

Let us remind you that SOKOL is a professional Russian solution for the protection of cable ducts based on the address-parallel method of sensor monitoring. The system successfully passed a year-long test cycle at real facilities of the Perm TUES PFE OJSC Uralsvyazinform. The uniqueness of the SOKOL system is that it allows targeted control of 60 tamper sensors on one two-wire line 20 km long with any number of branches (parallel connections) and any topology (star, tree, ring, mixed, linear). The system compares favorably with analogues in its highest reliability, confirmed during operation, ease of installation and maintenance, protection against breaks and short circuits, as well as cost-effectiveness.

The hardware system consists of object devices (as a rule, these are cable and communication well security units BOX with MKAD addressable sensor control modules installed in them), installed on the automatic telephone exchange in the premises of the crossroads, and addressable tamper sensors (ATS), installed on the periphery, for example, in wells. There are also insulation units (BI) that provide protection of loops from short circuits. DAK opening sensors are active, i.e. They have a built-in microprocessor and a specific operating algorithm, and are also non-polar in terms of connection to the loop. Moreover, when connected, the address is assigned to them automatically - there is no need to program anything. Addressable sensors operate independently of each other, i.e. when one is triggered, all the others remain protected. In addition, thanks to the possibility of organizing a “star” topology in the SOKOL subsystem, the loop can be protected from breakage: if there is a break in one place, all sensors remain protected; if there is a break in two or more places, only the disconnected segment will go out of control. Using optionally supplied BI insulation blocks, you can protect the loop from short circuits: in the event of a short circuit, the system will automatically turn off the damaged section of the loop, and all other sensors will be monitored.

Thus, "SOKOL" is simply an ideal means of protecting such small and grouped objects as cabinets. And if you study the issue more deeply, it is also the only possible one from the point of view of modern technology and logic.

Indeed, what, in essence, is the difference between the protection of wells on a cable route and the protection of “passive” cabinets in the entrances of residential buildings? By and large, nothing, with the only caveat that guarding cabinets in hallways is, perhaps, even easier than guarding KKS. Therefore, it is cheaper. This is due to lower wire consumption, no need for sealing, and ease of installation and setup of the system.

The only question is how to link the sensors, even if they are included in a common loop inside a residential building, with a control unit installed on a telephone exchange, which may be located several kilometers away? This is where it becomes clear why this solution is most suitable for Svyazinvest operators and other operators with traditional networks. Such operators, as a rule, have an impressive amount of installed capacity of fixed-line subscriber lines - copper pairs going from the station through distribution cabinets and boxes directly to subscribers' apartments. Among these pairs, in most cases, it was possible to find free ones before, and in recent years, when there has been a transition of subscribers from fixed-line to other types of communications, this resource has been released even more. In short, there are practically no problems with the allocation of free copper pairs in subscriber cables from telephone exchanges to residential buildings. Just such a pair can be used to organize a security loop for cabinets in a residential building. It is enough to feed this pair directly into the distribution box of the KRTP to the alarm loop, and at the station from the cross connect it to the control unit and that’s it, the system is ready!

It turns out that instead of active security equipment for tamper control in PON cabinets, addressable sensors DAK of the SOKOL subsystem are used, operating via a two-wire loop. The loop transmits signals from the sensors and simultaneously powers them. Sealing of the sensors is not required; electrical insulation of the spliced ends of the wire is sufficient. The sensors themselves are manufactured in such a way that they do not require any complex operations at the installation and connection stage. The loop inside the building is laid with a single-pair copper wire, for example, KSPV 2x0.5 or PRPPM 2x0.9, or even with ordinary telephone “noodles”. Wires can be laid along the internal communications of the building in convenient places (in shafts, risers, cable ducts, suspended ceilings, etc.), as well as externally. It is possible that the “noodle” will be the most convenient wire for this. And what? The wire is strong, can be nailed to regular nails, has suitable characteristics and cross-section, and most importantly, a minimum price. And operators almost always have such a wire in stock.

In the KRTP distribution box, the cable is connected to a dedicated pair, and that, in turn, to the BOX equipment installed on the telephone exchange.

The capabilities of the BOX block to implement the functions of the SOKOL subsystem make it possible to control 60 addressable sensors on one two-wire loop up to 20 km long with any number of branches and various topologies (ring, star, tree, linear, mixed). Depending on the configuration of the BOX, there can be from 1 to 4 such loops on one block. Those. up to 60, 120, 180, 240 addressable control points on one device. The device is also complete in terms of data transfer functions, because on board the BOX there is a standard Ethernet port with the TCP/IP protocol, which can be included in the operator’s multiservice network for data transfer to the Server and workstations.

We get an addressable parallel system for protecting PON cabinets, operating over one two-wire loop at a distance of 20 km from the telephone exchange to the cabinet, and has protection against short circuits and breaks. Moreover, the system satisfies the most stringent modern criteria and requirements imposed by operators on suppliers:

the solution is highly effective: instead of abandoning security and saving “on matches” (from the often encountered position in the spirit of “let’s look first, and if there is vandalism, then we will protect”), it is now easier and more profitable for the operator to initially include it in the package at minimal one-time costs cabinets with the appropriate sensors, having received a ready-made solution with a standard alarm system, and not later, during operation, take your specialists away from their main work to install non-standard protective equipment.

the solution is easy to install and unpretentious to maintain: maximum technological operations are performed at the stage of manufacturing sensors and cabinets, and the User can easily assemble a finished system using the simplest tools and materials, like a radio designer, and in the future it is just as easy to maintain it.

the solution is inexpensive: the presence of a security system and sensors does not significantly affect the cost of the cabinet, which operators and manufacturers strive to reduce to a minimum due to high competition in the broadband services market; in addition, the existing resources of the telecom operator are used to the maximum - copper wires receiving a “second life”, thus eliminating any additional costs.

The cost of the equipment is indicated directly in the figure, and if we take average figures, then the cost of the system per one protected PON cabinet is within 1000 rubles, which is two to three times more economical than the simplest solution for protecting active FTTB cabinets. And this cannot but rejoice, because the affordability of all components in the construction of PON networks is the main economic factor in the competitiveness of broadband access services and the success of the operator in the market.

Unique technology for protecting copper subscriber cables in FTTx broadband networks

FTTx technology in the construction of broadband access networks (BBA) is as common as mass theft of copper cables in the entrances of residential buildings. Massive cuttings of copper cables cause not only material damage associated with restoration work, network downtime, and unprovided traffic, but also damage to the reputation, image, and prestige of the operator. What does a good telecom operator want and should do? Drawing a loose analogy with sports, where you need to be “faster, higher, stronger,” the operator wants to develop and improve the quality of services and increase the customer base. However, he has to spend energy, time and money on “trauma treatment” - on repairing the damage.

CJSC NPC Computer Technologies, Russia's first developer of specialized systems for monitoring and security of communication networks, has always been at the forefront of manufacturers of equipment for protecting cable facilities and communication lines. We proposed and patented technologies for the protection of trunk and distribution cables with the determination of the location of a break based on free and occupied subscriber pairs as part of our APK "CENSOR" - the first professional Russian solution for comprehensive monitoring and protection of communication cables and LKS.

Time and again, taking care of the interests of our Clients - telecom operators and broadband services, confirming our status as a pioneer in our field, we have developed an innovative and unique technology “CRAB” for monitoring subscriber distribution cables in FTTx broadband networks.

A feature of FTTx broadband access networks is the presence of cabinets with equipment installed inside or near residential buildings and office buildings. From the operator's side, a fiber-optic cable enters the cabinet, and copper cables go from the cabinet to the subscribers. Often one cabinet is installed for the entire house or for several entrances, so inter-entrance and inter-floor connections are laid with a high-capacity multi-pair cable, which, on intermediate passive switches (cross-connects) installed in the entrances, is distributed into four-pair twisted pair Ethernet cables (UTP cat. 5e 4x2x0.53 or similar).

A new development of JSC Scientific and Production Center "Computer Technologies" is aimed at protecting copper distribution subscriber cables of the "twisted pair" type in FTTx broadband access networks with a subscriber access speed of 100 Mbit/s or 1 Gbit/s.

The “CRAB” subsystem consists of (highlighted in green in the figure): a special patch panel installed in the FTTx cabinet, a matching module made in the form of a network socket and installed at the subscriber, and an information collection device USI APK “CENSOR”. In this case, it is USI-8F “MAYAK”, designed specifically for monitoring and protecting broadband access cabinets.

Thus, the “CRAB” subsystem is suitable for both new Clients planning to purchase USI-8F, and all Clients already using these devices on their networks. In general, “CRAB” technology is supported by all devices in our line.

To protect subscriber cables, USI-8F must have the required number of free general-purpose inputs (according to the number of protected cables). There are a total of 8 of them on each control device, so even when connecting a door reed switch and a temperature sensor, there are still 6 inputs that can be used to protect communication lines. At the same time, you need to understand that it is not necessary to protect every subscriber line, but it is necessary to protect at least one such line in each inter-access multi-pair cable, which most often becomes the subject of theft. Then, based on rough calculations, we obtain a solution for protecting cables in 6-8 entrances of a residential building with one USI-8F device, which is very economical both in cost and in labor costs.

The AMP inputs are connected to the patch panel according to the diagram supplied with the equipment. The protected cable is also connected to the same patch panel. The technology is also unique in that it uses a busy subscriber line for security, and this saves communication lines.

The subscriber and his equipment do not feel such a connection in any way. The line is monitored without interference in the data transmission process, and only at the physical level, and the monitoring equipment is completely “transparent” for the end-to-end passage of traffic. For this purpose, a unique switching circuit specially developed at JSC Scientific and Production Center “Computer Technologies” is used, integrated into the patch panel and the matching module.

The “CRAB” matching module, made in the form of a regular network socket, is installed at the end of the protected cable section directly in the subscriber’s apartment or office. The network cable from the subscriber equipment is connected to it. At the same time, the “advanced” connection scheme “CRAB” allows you to protect the cable even when the subscriber equipment is disconnected from the network, i.e. The remote port is not connected.

If the cable breaks in the area from the patch panel to the matching module, the USI will issue a corresponding signal to the system, and this signal will be immediately transmitted to the dispatcher.

Thus, the operator has an effective and cost-effective solution to prevent mass thefts of communication cables in the entrances of residential buildings, and therefore the losses associated with this.

Needless to say, how important an indicator when implementing FTTx projects is their profitability and economic efficiency. These indicators can be jeopardized if the cable is cut, which will require the operator to additionally spend on its restoration. Now there is a real means to eliminate these risks and increase the profitability of projects for the construction of broadband networks - this is the “CRAB” subsystem of the “CENSOR” hardware and software complex.

New USI-4x4 device:

The construction of broadband access networks based on FTTB (fiber to the building) telecommunications cabinets opens up new opportunities for the operator and new services for the subscriber. At the same time, the operator has a complex and expensive network infrastructure, the stability and profitability of operation of which depends on the quality of control and management, and the reliability of its protection from external threats.

For mass monitoring and control on broadband networks, a simple and reliable solution is needed that provides control of life support parameters and protection of active FTTB broadband cabinets via an Ethernet network with management and resource accounting functions, support for the open SNMP protocol and proprietary software. It should have the advantages of leading existing solutions, and the cost should be at least half the price of the closest Russian analogues.

JSC Scientific and Production Center "Computer Technologies" has successfully coped with this task, and presents to the attention of Users a super-novelty - an economical data collection device USI-4x4 for monitoring active FTTB cabinets!

The new monitoring device USI-4x4 as part of the hardware-software complex "CENSOR" is intended for comprehensive technological control and security, management and accounting of resources in broadband access cabinets (FTTB) with active equipment.

The “off-road” formula “4x4” characterizes the main feature of the new USI-4x4: the device has four universal general-purpose input/output ports, configurable by the User for existing tasks. Each port can operate in “Input” mode - control of a sensor, or in “Output” mode - control of external equipment. Thus, USI-4x4 is suitable for any tasks and requirements for monitoring and protecting the Internet cabinets of a wide variety of Users - a real “all-terrain vehicle”!

Monitoring of active broadband access cabinets (FTTV). MAYAK-FTTx subsystem

The subsystem is designed to monitor and protect active cabinets of optical broadband networks. MAYAK-FTTx ensures compatibility with existing monitoring systems of telecom operators, including those from other manufacturers.

The new object device USI-8F "MAYAK" (F - Fiber) is designed for collecting, temporary storage and transmission to the center via Ethernet networks with TCP/IP and SNMP protocols of discrete information from small-sized FTTx telecommunication cabinets.

5.3 Security system against unauthorized access SIP telephony

SIP telephony is a modern alternative to traditional telephone communication.

The main advantage of SIP telephony is the ability to install telephones with a direct landline number and save significant amounts on long-distance and international calls.

Any subscriber with Internet access at a speed of 64 Kb/sec or higher can connect to SIP telephony services. To do this, just install one of the standard softphones on your computer, laptop or PDA, or buy any IP phone that looks very similar to traditional telephones, and is also convenient and easy to use, or an IP gateway (for connecting a regular phone, fax or integration with office PBX).

Connectivity becomes independent of a person's location, which can be compared to the process of receiving email.

The SIP protocol provides a high degree of protection of telephone conversations from eavesdropping and unauthorized access.

IP telephony standards and their security mechanisms

The lack of uniform accepted standards in this area does not allow the development of universal recommendations for the protection of IP telephony devices. Each workgroup or manufacturer approaches gateway and dispatcher security challenges differently, examining them carefully before selecting adequate security measures.

SIP Security

This protocol, similar to HTTP and used by subscriber points to establish connections (not necessarily telephone, but also, say, for games), does not have serious security and is focused on the use of third-party solutions (for example, PGP). As an authentication mechanism, RFC 2543 offers several options, including basic authentication (as in HTTP) and PGP-based authentication. In an attempt to improve the security of this protocol, Michael Thomas of Cisco Systems developed a draft IETF standard called the "SIP security framework" to describe external and internal threats to the SIP protocol and how to protect against them. These methods include protection at the transport level using TLS or IPSec.

6. Conclusion

Conclusion: In this course project, we implemented the construction of fiber optic lines using FTTB/FTTH technology.

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March 2012

General characteristics of the broadband access market in Russia

Rating of countries by the number of “home” broadband connections

Basic access network technologies

The J"son & Partners Consulting study focuses on the three most common groups of technologies: - FTTH (usually the xPON family of technologies is used) - FTTB - ADSL and ADSL 2+

GPON

FTTB

ADSL 2+

Penetration of access network technologies

Access network equipment

Development of GPON in the Russian broadband market

Detailed research results are presented in the full version of the report“Review of Fixed Access Network Technologies, 2011”²

Multiservice network technologies

FTTB subscriber access technology

1. Organization of an optical access network

1.1 Problem statement

1.2 Selection and justification of broadband access technology

FTTX

FTTB

FTTH

1.4 Communication scheme for FTTX technology

2. Selection and justification of the type of optical fiber and optical cable design

2.1 Selecting the type of optical fiber

2.2 Selecting an optical cable design

Cables type OKLST (with one PE sheath up to 192 RH) for laying in cable ducts

Cables type OKLZH-(T) (from 2 to 144 OV) for aerial installation (classic design, in accordance with TT FSK)

2.3 Selection and justification of cross-connect equipment

Block diagram of the FTTB access node configuration

Pigtail FC/PC SM (0.9) 1.5m

Block diagram of the PON P2MP aggregation node configuration

3. Selection and justification of equipment

3.1 Optical line terminal equipment

3.2 ONU equipment

Device versatility

Triple Play Services

VLAN and queue prioritization support

Support for virtual VLANs (802.1Q and port-based) is especially important for this device. Because it is this function that allows each type of traffic to be transmitted over its own virtual network.

The device also supports 802.1p queue prioritization to ensure proper quality of service, allowing users to use latency-sensitive applications such as audio/video streaming and VoIP over the network.

Safety

The ports of the Triple Play DIR-100 router, designed for connecting personal computers, are equipped with security functions. Thus, they have a built-in firewall to protect computers on the network from virus and DOS attacks.

4. Calculation of optical path parameters

4.1 Calculation of optical power budget for FTTB

4.2 Calculation of attenuation in the optical path for FTTB

4.3 Calculation of energy reserve for FTTB

4.5 Calculation of attenuation in the optical path for FTTH

5. Security system for FTTx technology

5.1 General provisions

The J"son & Partners Consulting study focuses on the three most common groups of technologies:
- FTTH (usually the xPON family of technologies is used)
- FTTB
- ADSL and ADSL 2+

Detailed research results are presented in the full version of the report
“Review of Fixed Access Network Technologies, 2011”²