Construction of a broadband access network using Ethernet technology. Description of FTTx connection technology from the Rostelecom operator FTTB technology connection diagram

Broadband Internet connection is a basic and in-demand service in the telecommunications industry today. The number of users with broadband access is growing every year and the bandwidth and capacity of broadband access is also increasing due to the high demand for this in the market.

Telecommunications companies today, when creating infrastructure, mainly invest, design and build broadband networks based on such advanced technologies as FTTB and PON.

FTTB subscriber access technology (translated from English as “fiber to the building”) is in great demand. It is distinguished by security and ease of coordination when deploying a network. Fiber optic cables and distribution networks of layer 2 nodes use a data network and an analogue cable television network. The equipment is specialized.

Its features:

— high reliability and low probability of failure;

— ease of building parallel digital networks;

— ease of implementation of new digital technologies;

— operation at low input optical powers;

The topology of this network consists of a data transmission node, a backbone fiber-optic communication line and a distribution network.

The use of FTTB technology requires the fulfillment of certain conditions for providing equipment with power supply and compliance with safety requirements, therefore this technology is often preferred by telecommunications companies in large and medium-sized cities. When designing a broadband access network based on FTTB technology, specialists need to make the most accurate calculations of subscriber density, since this affects the profitability of projects.

GPON technology is actively used by such providers as Megafon, Rostelecom, MGTS and others. This modern wired Internet access technology, providing high-speed Internet access up to 1 Gb/sec, with equal speeds of incoming and outgoing channels, is one of the most promising technologies of the family of passive optical networks (PON - Passive optical network (passive broadband access)).

The main idea of ​​the PON architecture is the use of just one transceiver module in the OLT (optical line terminal) to transmit information to multiple subscriber devices and receive information from them.

A large number of subscriber nodes can be connected to one OLT transceiver module. Their number can only be affected by the power budget and maximum speed transceiver equipment.

The flow of information from the OLT to the subscriber devices of the direct (downstream) stream is transmitted using waves with a length of 1490 nm. And data streams from subscriber nodes to the central node, together forming a reverse (upstream) stream, are transmitted at a wavelength of 1310 nm.

The television signal is transmitted with a wavelength of 1550 nm. OLT and ONT have built-in WDM multiplexers that separate outgoing and incoming streams.

The unique capabilities of passive optical networks are in optical “last mile” solutions and its further distribution for organizing high-speed optical access networks in urban multiservice communication networks.

Another high-speed successful technology is GEPON Ethernet Passive Optical Network (GEPON), based on the Gigabit Ethernet protocol. Information is transmitted at speeds of up to 1.2 Gbit/s.

Main advantages of GEPON technology:

— ease of installation and maintenance of equipment;

— the possibility of optimal use of the fiber-optic resource of the cable (connection of 64 subscriber devices to the PON branch);

— use of standard 802.3ah mechanisms to reduce the cost of equipment;

— increasing the transmission speed to 1 Gbit/s in both directions and providing more broadband services;

— providing QoS using 802.1p/TOS mechanisms.

— the ability to use mechanisms that allow the provision of services such as VoIP or VoD with a guarantee of quality;

— DBA (Dynamic Bandwidth Allocation) support;

— support for streaming video (IGMP Snooping).

FTTx technology from Rostelecom is one of the fastest and most reliable means for accessing the Internet. This connection is optimal for work large companies who need a stable network connection to support digital telephony, send and receive large amounts of data, such as video recordings, and many others corporate tasks. Rostelecom's FTTx technology is also not abandoned by individuals who want to get maximum opportunities and pleasure when using home boarding and interactive television, which has been gaining increasing popularity lately.

Rostelecom FTTx technology – what is it?

FTTx is one of the most promising Internet technologies that is being very actively developed by Rostelecom in large cities and beyond. The abbreviation stands for Fiber To The x, where x is any point, that is, your apartment, country house or office. In the Russian-speaking market, the technology often has a simplified name “”.

FTTx represents the general name of the technology line:

• FTTH (Fiber To The Home) – optical fiber is supplied directly to your home/apartment;
• FTTB (Fiber To The Building) - optical fiber reaches the building, and is then distributed to apartments using other technologies (Ethernet);
• FTTN (Fiber to the Node) – the fiber optic signal is distributed at the network node.
• FTTD (Fiber to the desktop) - the signal goes directly to the network user’s room (it is also called FTTS, where the last letter stands for Subscriber or subscriber in Russian).

What equipment is needed for FTTx Rostelecom

The Rostelecom provider in most cases installs FTTx equipment at nodes or in buildings, and then distributes the signal using switches via Ethernet technology. This option allows you to significantly reduce costs for the subscriber, but at the same time get a high connection speed. The FFTx line is capable of delivering multi-gigabit bandwidth and can thus provide every home user with a stable 100 Mbps connection. On the positive side This option, in addition to high speed and low cost, will also eliminate the need for installation special equipment in your apartment.

The subscriber can easily start using the Internet by connecting the cord to network card computer, or using a router to distribute the connection to several devices. In this case, the choice of router must be made based on its speed characteristics and the planned number of network devices. If you have computers and consoles (TV or game consoles) in your apartment that can be connected via an Ethernet cable, as well as devices that use Wi-Fi technology, you will need to purchase a router with wired routing capability and a built-in wireless access point. Such a device will allow you to organize a convenient home network based on FTTx technology from Rostelecom without complex configuration of a router and other equipment.

In cases where optical fiber is supplied directly to your apartment (FTTH), you will need to purchase a special modem that will allow you to decode the signal and transmit it to the Ehernet output. Further, the setup scheme will remain the same. When connecting fiber optics directly to the apartment, you can pay attention to modems, which immediately act as routers. This will free up space by getting rid of unnecessary network devices.

Setting up an Internet connection using FTTx technology

Depending on the type of FTTx, the connection setup from Rostelecom will be slightly different. In the case of FTTB, you will only need to order the service from the provider and rent or buy a router suitable for you.

When using, you will also need to have a fiber optic modem for setup. Usually, when laying the cable, the provider’s employees will install and configure the equipment themselves. It will be difficult to connect to a fiber-optic network without the help of a specialist, if only because crimping the laid cables can only be done with special equipment.

Thus, setting up FTTx connections from Rostelecom will differ significantly depending on the subtype and, of course, the equipment used.

Attention! Fiber optic modems have a very high cost, so when connecting to FTTx Internet, the provider often offers equipment for rent or credit.

FTTx technology from Rostelecom is very new and promising. Its use is already actively underway in large cities and beyond. The process for connecting to fiber optic internet may vary depending on the subtype of technology.

FTTB Internet connection technology is currently the most widespread in the world. In the early 2000s, it revolutionized the provision of provider services and remains the most popular due to its simplicity and reliability. But such a connection has limitations and disadvantages that must also be taken into account when connecting to the network.

What does FTTB mean?

Providing an Internet provider using FTTB technology always implies connecting an apartment building. On English the abbreviation stands for “Fiber to the building” - literally “Optical fiber to the house”. This is one of the variations of the use of FTTx technology, where “X” can mean either a large distribution node for an entire area or a separate end device, for example, a home computer.

If, when concluding an agreement with a provider, FTTB is mentioned, this means that a fiber optic cable is laid to the house. Then it is connected to a distribution node in the basement or on the roof of the building, and copper twisted pairs are laid to the apartments, which connect directly to a computer or to a router, which allows you to distribute Internet access to several devices at once.

Attention! Externally, the connection will look like a normal cable run from the entrance to the apartment without installing a modem. Just the cord and that's it.

What are the benefits of using FTTx?

This technology is used by all providers providing services in apartment buildings: Beeline, Rostelecom, MTS, Green Point and others. Main hallmark what will be used by FTTB are always served by beautiful sentences:

• speed up to 100 Mbps, allowing you to download movies in a matter of minutes and participate in online conferences and play online;
• unlimited Internet, no restrictions on traffic volume;
• possibility of connecting digital television and IP telephony via 1 cable.

All these possibilities appeared precisely thanks to the use of optical fiber using FTTB technology as the basis for providing network access.

What happened before?

The connection scheme using FTTB technology has become widespread for a reason. Those who used the Internet back in the last millennium remember that access was limited and the speed was very slow. In addition, the cord was connected through the telephone, which created additional restrictions.

These are all signs of using ADSL (“Asymmetric Digital Subscriber Line”). From a technical point of view, the difference was in the materials for the cord through which the signals are transmitted. Previously, instead of optical fiber, copper was used for this purpose. This good material, but it has several significant limitations:

1. Signal transmission speed. Unlike modern fiber optic schemes, ADSL only provided traffic at speeds of up to 24 Mbit/s. But this is in ideal conditions, but in fact it is several times lower.
2. Asymmetry of information transmission. 24 Mbit/s is for downloading files. And loading information onto the network was 8 times slower.
3. Interference. Bad weather, radiation from equipment or power lines constantly led to interruptions in communication.
4. Single threading. It was impossible to use the telephone and the Internet at the same time. Nobody even thought about the possibility of watching TV shows.

An optical cable does not have these disadvantages and, moreover, is cheaper to produce. Therefore, he gradually supplanted his predecessor.

What are the limitations of fiber optics?

Considering the differences ADSL technologies and FTTB, it is not surprising that the transition away from copper has provided greater network access opportunities and has become a foundation for development for ISP firms.

But the existing one at the moment The system also has several disadvantages that limit its distribution:

1. Price. Running fiber optic cable to your home and installing a distribution center costs money. That's why private sector and areas remote from the city center, as well as villages, remain without wired Internet.
2. Speed. Optical fiber is capable of transmitting information at a speed of 1 Gbit/sec, but the twisted pair cable distribution scheme reduces it by 10 times.
3. Streams. Internet, TV and telephony are the limit of FTTB connection technology. It is no longer possible to connect other systems to one cord and it is necessary to draw a separate line.

For city dwellers, the disadvantages of FTTB technology rarely cause inconvenience. And all the advantages of such a connection allow the existing scheme to successfully compete with other types of communication, including wireless.

What will change in the future

At the moment, large providers are already offering consumers new services that are provided not thanks to FTTB, but through PON technology(“passive fiber optic network”). The fundamental difference between these schemes is only in the refusal of copper twisted pair. This allows you to get rid of the distribution node and route the optical fiber directly to a separate house or apartment.

Important! PON and GPON are the same thing. The letter “G” only emphasizes the ability of optical fiber to transmit information at a speed of 1 Gbit/sec to attract customers.

When comparing connections using FTTB and GPON technology, the difference is not only in high speed. There are other important benefits of a passive fiber network:

1. Availability of a modem. If now to repair the unit it is necessary to open the panel located on the staircase or in the basement, then new scheme allows you to carry out all the necessary procedures without leaving your home, consulting by phone with the support service.
2. Possibility of point connection. PON provides a real opportunity to provide wired Internet in the private sector quite cheaply.
3. Multithreading. Many more systems can be connected to a passive fiber network at the same time.

But all the capabilities of GPON are not yet in great demand by clients, and 100 Mbit/s is quite enough for the average user. Therefore, providers will continue to use FTTB technology to serve the public in the coming years.

Multiservice network technologies

From 50% to 80% of funds are invested in the access network, therefore right choice technologies and network options are 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 various types 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 definitely in favor of FTTH solutions; they compare the duration life cycle investments in any access technology and a 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 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 a lot of money in software, cable structure 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 transmission interface 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 thought out standards for these technologies and availability necessary equipment enable the deployment of service provider networks 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 pressure 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 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 the 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.

A modern office is unthinkable without a computer. The number of home users is also steadily increasing. All this leads to a significant increase in demand for data transmission services: Internet access, dedicated channels, virtual networks, etc. The most promising Internet technology, one might say, the technology of tomorrow, is fiber-optic networks, the contours of whose development are emerging today. It's about about FTTx technology, the development of which is already on the agenda, which is a common name for two types of access - Fiber To The Home (FTTH - fiber optic cable to the house) and Fiber To The Building (FTTB) (fiber optic cable to the building; implied apartment building or office).

FTTx technology family

The FTTx family today includes several different subspecies:

FTTN(Fiber to the Node) - optics to a network node (usually a city or regional station or communication center);
FTTC(Fiber to the Curb) - optical fiber to a microdistrict, block or group of houses (this type of access technology is used for the construction of communication substations - the so-called extensions);
FTTB(Fiber to the Building) - fiber to the building (since the mid-2000s, all multi-storey and apartment buildings have been connected using this technology);
FTTH(Fiber to the Home) - optical fiber to the home (the most recent and progressive of architectures, which is just gaining momentum. Fiber is delivered directly to an apartment or private house).
In simple words, these subtypes differ essentially in how close the provider’s optical fiber comes to the user of the communication channel.

The most popular technology is FTTB

Modern Internet access technology - FTTB- stands for “Fiber to the Building”, that is, translated into Russian: “optical cable to the house, building”. The concept of FTTB describes a general approach to organizing cable infrastructure on an access network. According to it, an optical cable runs from the central hub of the telecom operator to a certain object (usually an apartment building or office building). It is included in a multiport switch. Well, then there is wiring to the subscriber using a regular copper twisted pair cable. At the time of writing, FTTB access technology is many times faster and more reliable compared to modern technologies and broadband access, including 3G/4G/LTE. It is also impossible not to note the possibility of upgrading the constructed network to support access speeds of up to 1Gb/s and 10 GB/s by replacing switches and end equipment. In this case, as a rule, the built optical infrastructure and home distribution network no need to change. Thanks to the development of FTTB technology, it has become possible to significantly expand the range of services provided to the subscriber, including:

Internet access (at speeds up to 100 Mbit/s);
- IPTV (viewing at least 100 channels MPEG2, MPEG4), HD, VoD);
- VoIP (for a number of users)

FTTB provides both a ring distribution model for switches and a star model, where switches are connected by spokes to aggregators, which allows you to build a high-performance network that is also scalable, flexible, secure and cost-effective.

What does FTTx technology give subscribers?

Reliable and high-quality communication.
The operation of a channel organized using FTTx access technology is not affected by weather conditions, third-party EM interference, there are no breaks and the speed does not drop. If there is no damage to the cable, then at the end you will always receive exactly the speed stated in the tariff.
High speed Internet access. Using the features of FTTx access technology allows ordinary subscribers to use speeds of up to 100 Mbit/s, and in some cases up to 1 Gbit/s, and also makes it possible to significantly increase the volume of transmitted information. The connection speed in this case is limited only tariff plan and speed local network inside a room or building.
Symmetrical channel. If you have ever used ADSL access, you know that the speed of the outgoing channel is much lower than the speed of the incoming channel. Sometimes this can be a very critical moment, especially when operating file-sharing networks when transferring large files. A symmetrical FTTx channel means the same high speed for the outgoing and incoming channels. This feature allows ordinary users to host game and web servers at home.

Connecting several communication services at once via one cable. This is the so-called “Tripple Play”, that is, if you wish, you can connect 3 services to one line at once: Internet, telephony and interactive digital television. At the same time, however, connecting a special access device - a router - is considered a prerequisite. The router must support VLAN separation technology by port (Example: Zyxel Keenetic, D-link DIR-300, Sagemcom 2804, 3804).

What is the advantage of FTTx technology over xDSL technology?

An optical cable has the advantage of allowing you to connect the Internet, telephone and cable TV with just one cable at a time: the bandwidth of the optical cable can easily cope with such a load.