INTRODUCTION

Not so long ago, working remotely was a challenge for an employer. But progress, as we all know, does not stand still and modern telecommunication technologies, every year more and more firmly enter our life. And it concerns rather a working life in which innovations constantly appear.

Currently, in any organization, in various areas of work, if the enterprise needs computers and there are more than two of them, then it is advisable to combine them into a local computer network. The computing network carries with it huge potential opportunities: acceleration of the production process; sharing of network elements; possibility quick access to the necessary information; reliable storage and backup of data; information protection; using the resources of modern technologies (Internet access, electronic document management systems, etc.)

A network is a group of computers connected to each other by communication channels. The channel provides data exchange within the network (i.e. data exchange between computers of a given group). A network can consist of two or three computers, or it can unite several thousand PCs.

Physically, data exchange between computers can be carried out via a special cable, telephone line, fiber-optic cable or radio channel.

The purpose of my course project is to organize and describe a local area network (LAN) of a service center with Internet access.

1 THEORICAL SECTION

.1 FUNCTIONAL DIAGRAM OF THE LOCAL COMPUTER NETWORK

.1.1 Analysis of the network structure and information needs of the enterprise.

The local area network (LAN) of the service center consists of a ground floor and a basement.

The organization of this network will use:

Power sockets

Switches

Server rack

Software

First floor:

Ground floor:

Power socket - 13

Hub - 2

Power socket - 26 Server rack - 1

Concentrator -3

Various information needs are foreseen for the network being created.

Such as:

· Local computing network

Internet access

· Ability to exchange information between users

· Database

1.2 PLANNING THE NETWORK STRUCTURE

.2.1 Computer network. Topology

Computer network (computer network, data transmission network<#"865298.files/image001.gif">

Figure 1. Types of network topologies

1.2.2 Star topology

Figure 2. Star topology

Star topology - topology view<#"865298.files/image003.gif">

Figure 3. Bus topology

local area network

The topology of the bus type (or, as it is also called, the common bus) by its very structure assumes the identity of the network equipment of computers, as well as the equality of all subscribers to access the network. Computers on the bus can transmit information only one by one, since the communication line in this case the only one. If several computers transmit information at the same time, it will be distorted as a result of overlap (conflict, collision). The bus always implements the so-called half duplex exchange mode (in both directions, but in turn, and not simultaneously).

In the bus topology, there is no clearly expressed central subscriber through which all information is transmitted, this increases its reliability (after all, if the center fails, the entire system controlled by it ceases to function). Adding new subscribers to the bus is fairly straightforward and usually possible even while the network is running. In most cases, using the bus requires a minimum amount of interconnect cable compared to other topologies.

Since there is no central subscriber, the resolution of possible conflicts in this case falls on the network equipment of each individual subscriber. As a result, the network hardware in the bus topology is more complex than in other topologies. Nevertheless, due to the widespread use of networks with a bus topology (primarily the most popular Ethernet network), the cost of network equipment is not too high.

Having considered the three main types of topologies, to build a project in our service center a mixed bus-to-star topology will be used. This topology provides high reliability, high performance, flexible administration options. According to all criteria, it meets the goals and objectives of the service center.

Figure 4. Mixed topology

1.3 NETWORK CONTROL METHODS

Depending on the scalability of the network, it will depend on how the network will be managed in a given enterprise. There are several control methods. Local computer networks are subdivided into two subgroups according to the management method: peer-to-peer and hierarchical (multi-level) networks.

1.3.1 Peer-to-peer networks

In a peer-to-peer network, all computers are equal: there is no hierarchy among computers and there is no dedicated server. Typically, each computer functions as both a client and a server; in other words, there is no separate computer responsible for administering the entire network. All users independently decide what data on their computer to make publicly available over the network.

Peer-to-peer networks are also called workgroups. A working group is a small team, therefore, in peer-to-peer networks, most often there are no more than 30 computers. Peer-to-peer networks are relatively simple.

Since each computer is both a client and a server, there is no need for a powerful central server or other components required for more complex networks.

Peer-to-peer networks are usually cheaper than server-based networks, but require more powerful (and more expensive) computers. In a peer-to-peer network, the performance and security requirements for network software are generally lower than in dedicated server networks.

Figure 5. Peer-to-peer network

1.3.2 Hierarchical networks

In hierarchical networks, there are one or more servers that store information that is shared by different users. In order to increase the reliability of information storage, two disks working in parallel and duplicating each other can be installed on the server,

in this case, in case of failure of one of them, the other is automatically included in the work. Depending on how the server is used in hierarchical networks, the following types of servers are distinguished:

File server. In this case, the server contains shared files and / or shared programs. One example of using a file server is to host MS Office programs on it. In this case, only a small (client) part of these programs is located on the workstations, which requires insignificant resources. Programs that allow this mode of operation are called network-installable programs.

Database server. In this case, the server hosts a database (for example, Consultant Plus, Garant, Bank customer accounts, etc.). The database on the server can be replenished from various workstations and / or provide information upon requests from a workstation.

Clients of the Hierarchical Network can use OS: Windows XP, Windows Vista, Windows 7, servers require special server versions of operating systems.

Figure 6. Hierarchical network

Our service center will use a hierarchical network. For our case, this is the most suitable option. To prevent our network from becoming an information "garbage dump", as well as to increase the reliability of information storage, it is necessary to have several servers. In this case, a file server, an internet server, and a database server. The server will host programs MS Office, 1C and others, and on workstations, there will be only a small (client) part of these programs that require insignificant resources. It is also necessary for each user to allocate his rights in the local network.

1.4 NETWORK ORGANIZATION BASED ON A NETWORK OPERATING SYSTEM

.4.1 Selecting an Operating System

When choosing an Operating System, you need to know for what purposes it will be used. Here it is necessary to take into account which network is Peer-to-Peer or Hierarchical. Currently, there are many operating systems For example:

Windows familiesWindows 2000 / NT ... server 2003/2008 ... .XP / 7/8 ...

Also Linux families

We need our OS to be:

1. Stable

2. Had good protection

Easy to operate

Had a good speed of work

5. Supports over 4GB of RAM

Nothing superfluous

Windows Server 2003, available in four major editions, each targeting a specific market sector.

All of these editions, with the exception of the Web Edition, are also available in 64-bit (AMD64<#"865298.files/image009.gif">

Figure 7.1 - hey configuration step

Figure 8.2 - nd stage of setup

Figure 9.3rd stage of setup

This completes the computer setup<#"865298.files/image013.gif">

Figure 11.1 connection option

Figure 12.2 - connection option

Setting up: Consider the first option for setting up the printer.

1. In the Start menu, click Settings> Printers and Faxes

2. On the left side of the Printers and Faxes window, in the Printing Tasks section, to start the wizard that helps you install a printer, click Add Printer.

In a window with a subtitle Local printer or connecting to a printer, select a Network printer or a printer connected to another computer and click the Next> button.

4. In the window with the subtitle: Specify a printer, select Connect to a printer or browse printers ("Next" button). In the "Name" field, print the path to the network printer.

For example: \\ base \ elephant (this is the 4th floor printer, HP LaserJet 9000dn)

Figure 13. Add Printer Wizard

5. In the window with the Browse printers subtitle, in the Shared printers field, select Network Microsoft Windows> MI> BASE and there we select the printer that needs to be connected. For example: elephant (this is a ground floor printer, HP LaserJet 9000dn). Next>

6. In the window with the subtitle Printer by default, select whether or not to use this printer by default. When printing from any application, if no other printer is selected, the printed documents will always be sent to the default printer. Next>.

7. In the window with the subtitle Completing the Add Printer Wizard, click Finish.

1.7 CONFIGURING NOD 32 ANTI-VIRUS SYSTEM

Having an antivirus program on the server, it must be configured so that anti-virus database on client machines was updated automatically and by local network.

Let's start configuring: At the very beginning, we need to configure server updates via the Internet. On the server, open the program window - NOD 32. Go to the section: Settings> Updates, the "Automatic update settings" window will open, on the "Location" tab, click the "Servers" button and enter your update server, which is attached to the anti-virus system disk. Then we enter our name and password, which is also attached to the disk. The second step is to set up the "Mirror".

Figure 14. Configuring antivirus

A mirror is a folder on the server that client computers will access via the local network to update anti-virus programs. To do this: go to the mirror tabs, go to the settings. In the window that appears, check the "create update mirror" checkbox, click on the "Folder" button, create a folder on the C: \ drive, write a name for it, for example, "NOD obnov", click OK. You need to go to the "Advanced" section and see which port is used to provide files via HTTР (2221), click OK. On the client machine, open the antivirus program window> updates> Locations> Servers> Add>: //192.168.98.1 : 2221 that is, it prescribes the IP address of our server and the HTTP port of the server, click OK. Then select our server from the drop-down list and click OK.

1.8 NETWORK RESOURCES

Almost at any rapidly developing enterprise, there is a local computer network, and the enterprise also has many peripheral devices, for example: Scanner, printer, plotter, non-standard peripheral device, terminals, depending on the direction of the enterprise. There is such a thing as a shared network resource.

A shared network resource is a device or piece of information that can be accessed remotely from another computer.<#"865298.files/image017.gif">

Figure 11. Fiber optic cable

At the heart of each of them is a core made of germanium and silicon, covered on top with a silicon shell, cladding and outer coating.

Several layers of buffer skins help to reduce mechanical stress (friction, stretching, bending, etc.) on the core. The outer shell protects it from temperature changes, humidity, dust and other external adverse factors. The number of optical fibers in a cable may vary. Traditionally, 4, 6, 8, 12, 16, 24, 32, 48 - fiber cables are produced. Depending on the type of fiber, optical cables are divided into: single-mode and multi-mode.

2.1.4. Twisted pair

Twisted pair - cable type<#"865298.files/image018.gif">

Figure 12. Twisted pair

Unshielded twisted pair: Twisting of conductors is performed in order to increase the degree of connection between each other, conductors of one pair and subsequently reduce electromagnetic interference<#"865298.files/image019.gif">

Figure 13. Cable - channel

2.2 TECHNOLOGY OF CABLE LAYING

.2.1 Routing Fiber Optic Cable

The optical cable runs along the lighting poles to the end wall of the building, at the level of the second floor. Then it is attached to the end wall of the building with metal brackets.

Figure 14. Fiber-optic routing

Through the end wall, the fiber-optic cable gets into a special corrugated pipe, it is both additional protection and insulation of the main cable. Then, through a corrugated pipe, the cable enters the room where the SHKOS (Optical Cross Rack Cabinet) is installed, it is intended for termination, distribution and switching of optical communication cables.

Figure 15. ShKOS

From the output ports, through a special fiber-optic patch cord, the fiber itself goes to the media converter. A media converter is a device that converts a signal propagation medium from one type to another. The most common medium for signal propagation are copper wires and optical cables. In our case, the media converter converts the light signal coming out of the optical fiber into an electrical signal, which will be further transmitted through copper cables. Twisted pair wiring technology

A shielded twisted pair is connected to the output of the media converter, to the Rj - 45 connector. The second end of the twisted pair cable from the first floor goes down to the ground floor via a cable channel. Since the ceiling of the basement is hinged, consisting of a metal frame and gypsum boards. The twisted pair cable will be installed on the inside of the false ceiling.

Figure 16. Suspended ceiling

The cable runs along the suspended ceiling to the office where the "server cabinet" telecommunication cabinet is located. Where then the cable, twisted pair, is connected to the router, since this cable is used to access the Internet.

2.3 TELECOMMUNICATION CABINET

A telecommunication cabinet, also known as a "server cabinet", is the cabinet itself, made of aluminum alloy, which makes it lightweight, on which it reliably houses: passive and active network equipment, it provides convenient access to all network equipment. It is also easy to install and install in a variety of commercial environments. Cabinets can be open or closed, this project uses an open telecommunications cabinet.

Figure 17. Server rack

2.3.1 Organization of communication lines in a telecommunication cabinet

A twisted pair cable is connected to the first network card of the Internet server, leaving the router, it receives Internet traffic. The second network card is connected to the hub using a patch cord, it distributes Internet traffic throughout the network. All available servers are connected to the hub, in our case it is a file server and a database server.

On the rear side of the patch panel there are so-called IDC connectors (insulation displacement connector), to which the twisted pair cable is connected. This is the cable that comes from client machines and external switches.

Figure 18. Patch panel. Rear side

On the front side of the patch panel there are many ports, the most commonly used number being 12, 24, 25.

Figure 19. Patch panel. Front side

Figure 20. Hub connected by patch cords with a patch panel

We have client machines and external switches connected to the patch panel on the back side. There are ports on the front side. Each port is connected to a separate machine. Patch with a cord, connect the patch panel to the hub. Above each port of the patch panel, we sign the number of the cabinet where the client machine connected to this port is located. Also, when laying a twisted pair, we mark the two ends, then to figure out where which cable is. For example, it can be digital marking, i.e. to one end of the wire we hook a tag with the number "1" and mark the other end with the number "1". In the event of a network break, we are able to easily determine which machine is connected to the corresponding port, on the patch panel, as well as which wire. This allows us to reduce the time spent looking for a damaged cable.

Figure 21. Cable marking

Figure 22: Cable routing

On the back side of the patch panel, the twisted pair is brought out under the suspended ceiling, because that is where we will have all the wires, up to the office where a local network is needed. Then, in the wall of the office, where you need to lay the network, a through hole is drilled between the suspended ceiling and the usual one. A corrugated pipe is inserted into the hole. A cable is pulled through the hole. In the office where the client machines will be located, cable channels are installed in advance, in which the twisted pair and power cable will be located. Then, we lay the cables in the cable ducts. We install the power cable into the power outlet to provide this cabinet with electricity. We mount the twisted pair cable into special network sockets "RJ-45".

2.3.2 Mounting the twisted pair, to a network socket RJ - 45

1. For installation we will use: RJ-45 socket<#"865298.files/image029.gif">

Figure 23. Crimping the cable

Figure 24. Required tools

2.4 TECHNOLOGY OF CREATING A PATCH CORD

We take the end of the twisted-pair cable from the coil. We measure the segment of the required length: the cable should freely reach from the computer to the switch, without blocking the passage. It is advisable to calculate the length of the cable so that later you can put it in its box or hide it behind the baseboard.

Carefully remove the upper protective layer (outer insulation) of the cut cable. If there is a thread or insulating foil, then cut them off. The insulation is removed at a length of approximately 30-40 mm from the end of the electrical cord. After we removed the top winding of the cable, we see eight strands of wires that differ from each other in color. They are twisted in pairs.

We straighten each wire. All wires must be absolutely flat, straight and clearly separated from each other. Next, we compose these eight colored wires together (tightly and in one line) in a certain sequence. The sequence is as follows (T568B), from left to right, as shown in the figure:

Figure 25. Crimping twisted pair

We proceed to crimping the ends of the cable. We need crimping pliers. We carefully support the end of your wires: Take the connector. It must be turned with the tongue down, and the contacts up (picture). Holding the contacts, carefully insert the end of the cable all the way into the connector, so that each wire gets into its own connector track. After making sure that the contacts are in the correct position, we place the connector in the crimping pliers. They have a dedicated connector. Holding the cable, we squeeze the pliers all the way - all contacts should be well "squeezed". We take out the ready-made, crimped connector from the ticks. With the second end of the cable, we repeat the same thing as with the first. Now we need to check our patch cord. We take the tester and insert the patch cord into it with both ends. If the indicators on both devices match, then the patch cord is ready for use.

2.5 COMPUTER NETWORK COMMUNICATION EQUIPMENT

To connect computers to a local network, communication equipment is used. Depending on the scalability of the network, it will depend on what equipment and how much must be used to organize a LAN.

In my network, the following communication equipment is used to connect computers to a local network:

Network cards (adapter, network adapter) are expansion cards that plug into expansion ports on motherboard computer. O The main function is the transmission and reception of information over the network.

A router is a device used to organize large local networks. Provides traffic between local networks with different network addresses. Routers help reduce network congestion by dividing it into collision domains and broadcast domains, and by filtering packets. They are mainly used to combine networks of different types, often incompatible in architecture and protocols, for example, to combine local Ethernet networks and WAN connections using xDSL, PPP, ATM, Frame relay, etc. Often a router is used to provide access from a local network to the global Internet, performing the functions of address translation and firewall.

Figure 26. Hub Figure 27. Router

2.6 CALCULATION OF COSTS OF CREATION OF A NETWORK

2.6.1 Determination of the cost of the material part of the network

Table 1 Cost of all equipment

CONCLUSION

In this course project, we examined the basic issues of creating a local area network at an enterprise. In our case, we organized a local area network in the service center.

There are 39 workstations in our network. Our network has a hierarchical structure, built on a mixed bus-star topology, which means that the entire network will be managed through specially designated computers, the so-called servers. To ensure the security of information, integrity and quick accessibility to information in our network, we use four servers. Internet server, database server, two file servers, one of them is backup.

Hubs are the main device connecting different parts of the network into a single network. There are two types of cables, twisted pair and fiber optic cables. The cable is laid through cable ducts and along the suspended ceiling.

Based on all of the above, we can conclude that this network is very reliable, but requires constant maintenance. The cost of building the network was 287,457.0 rubles.

LIST OF SOURCES USED

1 Kosarev V.P. "Computers and Networks"

2

Kirov Regional State Educational

budgetary institution of secondary vocational education

"Kirov Aviation College"

Local area network of an enterprise

Student of group B-32

K.V. Osotova

Teacher

Kirillova L.A.

Introduction

For the first time, the idea of ​​connecting several independently operating computers into a single distributed computing system came to engineers back in the mid-60s of the XX century. And the first successful experiment on transferring discrete data packets between two computers was carried out in 1965 by a young researcher from the Lincoln laboratory of the Massachusetts Institute of Technology Larry Roberts. The data transmission algorithms proposed by Roberts largely served as the basis for the ARPANet global computing network, built in 1969 at the initiative of the American Advanced Research Projects Agency (ARPA), and it subsequently, merging with several other existing at that time networks, has become the foundation on which the modern Internet has grown.

The ultra-fast development of computer technology has led to a huge increase in the computer park.

A local area network (LAN) is a collection of computers and other computing equipment (active network equipment, printers, scanners, etc.), connected by cables and network adapters and running a network operating system.

If computers are not geographically separated (located within one or two buildings), then it is easy to organize a local area network, which will be economically viable.

The advantages of creating a local network are many: such a network can be used for word processing, act as its own information system, an external database, to perform numerical calculations, be an information system in management, planning, accounting, design, etc.

The main components of a LAN are:

workstations;

interface boards;

network servers;

Each of the LAN devices is connected to a data cable that allows them to communicate.

The aim of the course project is to create a college computer network, which consists of eight buildings, each of which consists of two floors, which should be able to provide network users with the sharing of resources of all computers. There are 2 workgroups on the floor, each of which includes 10 workstations.

The developed local area network must meet the requirements of reliability, speed and expandability.

1 Analysis of the design assignment

1.1 Initial data

1.1.1 Survey of the selected room

The goal of the project is to design a computer network for the college. It includes 8 buildings with 2 floors. The distance between buildings is shown in Figure 1 (in meters).

Figure 1 - Layout of college buildings

1.1.2 Location of computers in workgroups

Table 1 - Distribution of workstations

1.2 Choice of technology

Network technologies can significantly increase the efficiency of the use of computers, allowing you to create information systems that provide a solution to the problems of remote and automated learning, information storage, workflow, messaging and organization group work over projects.

It is important to make a reasonable choice of the structure of the college's local area network, which allows not only to quickly build a simple and fairly effective information system, but also to choose a solution that will reduce the cost of effort and resources, allowing to distribute the load between the computing networks of college departments.

Ethernet is one of the most common technologies used in computer networks. Today, most network adapters are equipped with interfaces that support speeds of 100 Mbps, 1 Gbps, 10 Gbps.

Advantages of using technologies in control systems:

- reduction in the cost of jobs - no need to develop or pay for specialized software in the workplace;

- reduction in the cost of support - achieved due to the lack of specialized software at workplaces;

- reduction in the cost of remote monitoring - the use of publicly available communication channels allows monitoring with minimal costs for organizing connection to the system;

- simplification of personnel training - achieved by using a uniform user interface at all workplaces;

- simplification of integration with external ISs - the use of open standards allows you to integrate with systems built using similar technology;

Disadvantages:

- the lack of a guaranteed time for delivery of information - there is a whole class of objects for which control in hard real time is required, in this case additional costs are required for the reservation of the necessary bandwidth channels, which is not always cost effective;

- lack of standardized means of protecting information - additional costs are assumed for the development of a proprietary system for differentiating access to resources and protecting information in public networks;

- development of telecommunication and network technologies.

FastEthernet (IEEE 802.3u) technology is an evolutionary development of the classic Ethernet technologies... Its main advantages are:

- increasing the bandwidth of network segments up to 100 Mb / s;

- saving the Ethernet random access method;

- preservation of the star-shaped network topology and support for traditional data transmission media - twisted pair and fiber-optic cable.

These properties allow for a gradual transition from 10Base-T networks - the most popular Ethernet option today - to high-speed networks that maintain a significant continuity with a well-known technology: FastEthernet does not require a radical retraining of personnel and replacement of equipment at all network nodes. The official 100Base-T (802.3u) standard has established three different specifications for the physical layer (in terms of the seven-layer OSI model) to support the following types of cabling systems:

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

- 100Base-T4 for a four-pair cable on an unshielded twisted pair UTP Category 3, 4 or 5;

- 100Base-FX for multimode fiber optic cable.

1.3 Topology selection

The term topology, or network topology, refers to the physical location of computers, cables, and other components of a network. The topology of the network determines its characteristics. In particular, the choice of a particular topology affects:

- on the composition of the required network equipment;

- on the characteristics of network equipment;

- on the possibility of expanding the network;

- on the method of network management.

Each network topology imposes a number of conditions. For example, it can dictate not only the type of cable, but also the way it is laid. Topology can also determine the way computers interact on a network. Different types of topologies correspond to different methods interactions, and these methods have a large impact on the network.

There are 3 basic topologies:

- bus - is a common cable (called a bus or backbone) to which all workstations are connected. There are terminators at the ends of the cable to prevent signal reflection.

- a ring is a topology in which each computer is connected by communication lines with only two others: from one it only receives information, and to the other it only transmits. On each communication line, only one transmitter and one receiver works. This eliminates the need for external terminators.

- star - the basic topology of a computer network, in which all computers on the network are connected to a central node (usually a switch), forming a physical network segment. Such a network segment can function both separately and as part of a complex network topology (usually a “tree”). All information exchange is carried out exclusively through the central computer, on which a very large load is imposed in this way, therefore it cannot be engaged in anything other than the network. As a rule, it is the central computer that is the most powerful, and it is on it that all the functions of managing the exchange are entrusted. In principle, no conflicts in a network with a star topology are possible, because the management is completely centralized.

Star topology - In star networks, network media connects a central hub to every device connected to the network. This topology uses central point control, and communication between devices connected to the network occurs via point-to-point links between each device and the center channel or hub. All network traffic in a star topology goes through a hub. First, the data is sent to the hub, and then the hub forwards it to the device according to the address contained in the data. In star networks, a hub can be active or passive:

- passive - connects sections of the network data transmission medium;

- the active concentrator not only connects the sections of the transmission medium, but also regenerates the signal, i.e. works like a multiport repeater. By performing signal regeneration, an active hub allows data to travel over greater distances.

Star topology benefits:

- ease of maintenance: the only area of ​​concentration is the center of the network;

- allows you to easily diagnose problems and change the gasket scheme;

- simple in terms of design and installation;

- reliability - if one of the sections of the network data transmission medium is cut off or short-circuited, then only the device connected to this point loses communication. The rest of the network will function normally;

- easy to add workstations.

In a sense, the advantages of the star topology can be considered as its disadvantages. For example, having a separate piece of cable for each device makes it easy to diagnose failures, however, this also leads to an increase in the number of pieces. This increases the cost of installing a star network. Another example: a hub can simplify maintenance because all data flows through this central point; however, if a hub fails, the entire network stops working. This topology is suitable for this task.

1.4 Choice of cabling

The basis for choosing a cabling system is the development of specifications. communication equipment in a computer network of work premises with an indication of the location of PCs and cable lines in them.

The choice of a cable system depends on the intensity of network traffic, requirements for information protection, maximum distance, requirements for cable characteristics, and the cost of implementation.

Twisted pair (twistedpair) - a type of communication cable, is one or more pairs of insulated conductors, twisted together and covered with a plastic sheath. Typically Ethernet 10Base-T uses a twisted pair cable. One transmit and one receive (AWG 24).

Thin coaxial (RG-58 or "Thin Ethernet") is an electrical cable consisting of a center conductor and a shield and is used to transmit high-frequency signals. Characteristic impedance 50 Ohm, diameter 0.25 inches, maximum length of the cable segment 185 meters. Rule 5.4.3, 10BASE2 standard applies. Coaxial cable is more noise-resistant, signal attenuation in it is less than in twisted pair.

Optical fiber is an optical waveguide - a round rod made of an optically transparent dielectric. Due to their small cross-sectional dimensions, optical waveguides are commonly referred to as fiber-optic LEDs or optical fibers.

After analyzing the characteristics different types cable, physical location of computers, choose a 10Base-T twisted pair cable and fiber optic. Twisted pair and fiber optic complement each other, so they can be used together. In this case, the fiber-optic cable is for building the backbone, and the twisted pair is for creating a network inside the premises.

Equally important in the design of a computer network is the choice of a cable subsystem, since a reliable aircraft provides reliable connections. All connections in the network must be performed efficiently, unreliable contacts and others are unacceptable physical damage... Important attention is paid to this, because finding an open or damaged connection in a faulty network is a very time-consuming task.

The cable system is the most important physical medium that connects computers into a single whole, without which the functioning of the local network as such is impossible.

The importance of the cable system is determined not only by its fundamental nature in the construction of computer networks, but also by the fact that the wrong choice of a network cable can lead to a significant decrease in network performance or its incorrect operation. That is why it is extremely important to choose the right network cable, to build a cable system competently and professionally. Recently, structured cabling has been increasingly used as such a reliable basis.

A structured cabling system (SCS) is a set of switching elements (cables, connectors, connectors, cross-over panels and cabinets), as well as a technique for their joint use, which allows you to create regular, easily expandable communication structures in computer networks.

SCS differs in that, if necessary, the configuration of connections in the network can be easily changed, that is, add a switch, computer, segment, etc. The structured cabling system is built in such a way that each workplace must have sockets for connecting workstations to them. This can save money in the future, as changes in the connection of new devices can be made by re-connecting existing cables. Such a system is built hierarchically, with the main highway and numerous branches from it.

The main principle of SCS is that it should cover the entire building.

Using SCS instead of chaotically laid cables gives many advantages:

- versatility - SCS can become a single medium for transferring computer data in a local computer network, organizing a local telephone, transferring video information, if its organization is clearly thought out;

- increased service life - the aging period can be 10 - 15 years, which is even very good;

- the ability to easily expand the network;

- it is possible to change the cable type in a separate subnet independently of the rest of the network;

- reliability - SCS has increased reliability, since the manufacturer of such a system guarantees not only the quality of its individual components, but also their compatibility.

SCS includes a horizontal subsystem (within a floor), a vertical subsystem (between floors), a campus subsystem (within one territory with several buildings).

1.5 Horizontal subsystem

The horizontal subsystem is characterized by big amount branch cables, as it must be routed to each user outlet. Therefore, for the cable used in horizontal wiring, increased requirements are imposed on the convenience of making branches, as well as the convenience of laying it indoors. When choosing a cable, the following characteristics are taken into account: bandwidth, distance, physical security, electromagnetic interference immunity, cost.

The preferred medium for horizontal cabling is twisted pair, both shielded (STP) and unshielded (UTP).

Category 5 UTP is an unshielded copper cable made up of four cable pairs, each with a color and pitch. Usually two pairs are for data transmission and two for voice transmission.

STP is a twisted pair of wires that are wrapped in an insulating shield. This cable allows data to be transmitted over a longer distance and supports more nodes than UTP. The presence of the screen makes it more expensive, but it has good noise immunity and protects the data from electromagnetic radiation.

The cable for the horizontal subsystem of this network is twisted pair UTP cat.5.

1.6 Vertical subsystem

The vertical subsystem cable that connects the floors of the building must transmit data over long distances and at a faster speed than the horizontal subsystem cable. It consists of longer cable lengths, the number of branches is much less than in the horizontal subsystem.

This network uses a fiber optic cable for these purposes.

1.7 Campus subsystem

The campus subsystem of this network is an interconnection of several buildings with the help of a cable duct, laying an external fiber-optic cable.

2 Description of the block diagram

In accordance with the initial data selected by the topology and technology of the network, the cable system, a structural diagram of the local computer network has been developed, which is shown in drawing 230106.KPSD05.018E1.

The network consists of eight buildings. The connection between them is carried out using the GigabitEthernet technology, since this technology provides traffic up to 1000Mbps. Fiber optic cable is used to connect buildings.

To provide the necessary traffic up to 100 Mbit / s, Fast Ethernet technology is used in all buildings. Workstations in a workgroup are connected through switches. All switches of groups of one floor are connected to a floor switch. Further, communication between them is carried out through the building switch. This switch must have at least one optical port to connect to the main switch in the server room. A twisted pair cable is used to connect the switches.

The network in Building 1 includes a server room that houses the InternetServer, DataServer, and the main switch. All other buildings, except for floor switches, are connected to it. In addition to the usual ports, the main switch must have four optical ports in order to be able to connect all buildings through an optical cable.

The first working group includes 15 workstations on the first floor, the second group - 15, the third - 10 computers on the second. There are four (1,2,3,4) Gigabit Ethernet switches in the building. The main Gigabit Ethernet switch with fiber optic is located on the ground floor, which connects all workgroups in the building and establishes a fiber optic connection through the duct to the second, third and fourth buildings. The working groups of the building are united by switch 1. Also on the first floor of building 1 there is a main server serving for network administration and program control of the network operation, establishes a connection with the provider using an ADSL modem.

On the first floor of building 5, the switch establishes a similar connection to buildings 6,7,8. The network in buildings 1 and 5 is interconnected using switches and fiber optic. Also on the ground floor there is the main server, which serves for network administration and software control of the network operation, establishes a connection with the provider using an ADSL modem.

The network in buildings 2,3,4,6,7,8 includes 2 workgroups on the first and second floors, each of which includes 10 workstations, therefore they are united by one switch. In total, buildings have five Gigabit Ethernet switches, the main Gigabit Ethernet switches with fiber optic are located on the first floors of buildings, which connect all departments of each building, and are connected via fiber optic between adjacent ones.

3. Justification of the wiring diagram

Based on the structural diagram, the selected technology and network topology, cable system, a wiring diagram of the network was developed, shown in drawing 230106.

Switches located in workgroups must have 24 ports for twisted pair connection, of which 15 are the maximum number of workstations in the group, and the rest are for possible expansion of the local network. Workstations are connected to the workgroup switch through patch panels.

The switch connects to the patch panel through a 0.5 meter patch cord, then a 1.5 meter patch cord leads from the patch panel to an RJ-45 category 5e socket located directly in the workstation. Wall-mounted cabinets are used as wiring closets in workgroups and on floors.

Since there are 2 working groups on floors 1,2 of each building, the switches are interconnected using an unshielded twisted pair (UTP 5e) included in a special patch panel, from which the patch cord is connected to the common floor switch. The floor switches are connected in the building switch via a twisted pair (UTP 5e) that goes into the patch panel, from which the patch cord enters the building switch.

Each switch has a fiber optic input. The building switch is connected to a common LAN switch in the server room via a fiber optic cable (FO-ZIP-IN-50-2-FRPVC). The presence of fiber optic inputs on all switches allows this LAN to be expandable in the future.

The server room with Internet Server and Data Server is located in the first and fifth buildings on the first floor. The main switch has 4 additional optical ports to connect common switches in the rest of the buildings. The web server serves as a connection to the Internet using a fiber optic cable.

For fiber-optic connection between the provider's equipment and the server, it has an additional network card.

4. Choice of network equipment

4.1 Description of network equipment

There are many factors to consider when choosing network equipment, including:

- the level of equipment standardization and its compatibility with the most common by software;

- the speed of information transfer and the possibility of its further increase;

- possible network topologies and their combinations (bus, passive star, passive tree);

- method of control of exchange in the network (CSMA / CD, full duplex or marker method);

- permitted types of network cable, its maximum length, immunity from interference;

- the cost and technical characteristics of specific hardware (network adapters, transceivers, repeaters, hubs, switches).

Network equipment - devices that make up a computer network. Conventionally, there are two types of network equipment:

- active network equipment - equipment that is capable of processing or transforming information transmitted over the network. Such equipment includes network cards, routers, print servers;

- passive network equipment - equipment used for simple signal transmission at the physical layer. These are network cables, connectors and power outlets, repeaters and signal amplifiers.

To install a wired computer network, we first need:

- network cable and connectors (called connectors);

- network cards - one in each PC on the network, and two on a computer serving as a server for Internet access;

- a device or devices that transfer packets between computers on the network. For networks of three or more computers, you need special device-switch that unites all computers on the network;

- additional network devices. The simplest network is built without such equipment, however, when organizing a general Internet connection, using common network printers additional devices can make these tasks easier.

Currently, there is a diverse number of firms specializing in the production of network equipment. The network equipment market is represented by firms that have already won worldwide recognition in the quality and reliability of their products, and firms that have not yet fully established themselves in the world market, but have great prospects in their development. At the moment, the following dominate among the firms producing network equipment: Cisco, 3Com, HP, D-Link.

The equipment of the companies presented is rarely used in the construction of networks, and it is more rational to choose equipment from another company to ensure compatibility, since there are various forms and methods of control. With this in mind, we choose D-Link as a leading provider of innovative, practical and highly efficient voice and data network products, services and solutions for companies of all sizes and public sector organizations.

cable server computer montage

4.2 Network conductors

This group includes various network cables (twisted pair, coaxial cable, fiber optic). There are several categories of twisted-pair cables that are labeled from CAT1 to CAT7. In local networks of the Ethernet standard, twisted pair CAT5 is used. For work with twisted pair cables, RJ-45 connectors are used.

4.3 Network switches

Currently, switches (or, as they are called, switches) are used in local networks. These are devices that have their own processor, internal bus, and buffer memory. If a hub simply forwards packets from one port to all others, then the switch analyzes the addresses of the network cards connected to its ports and forwards the packet only to the correct port. As a result, useless traffic on the network is dramatically reduced. This can greatly increase network performance and provide faster data transfer rates in networks with a large number of users.

The switch can operate at 10, 100, or 1000 Mbps. This, as well as the network cards installed on computers, determines the speed of the network segment. Another characteristic of a switch is the number of ports. This determines the number of network devices that can be connected to the switch. In addition to computers, they are print servers, modems, network disk drives and other devices with a LAN interface.

When designing a network and choosing a switch, you need to take into account the possibility of expanding the network in the future - it is better to purchase a switch with a few more ports than the number of computers in your network at the moment. In addition, one port must be kept free in case of interconnection with another switch. At present, switches are connected by a conventional twisted pair of the fifth category, exactly the same that is used to connect each computer on the network to the switch.

4.4 Additional network equipment

In a local network, you can use various additional equipment, for example, to connect two networks or to protect the network from external attacks:

- a print server, or print server, is a device that allows you to connect a printer that does not have its own network port to the network;

- the repeater is designed to increase the distance network connection by amplifying the electrical signal;

If you will use a twisted pair cable longer than 100 meters in a local network, repeaters should be installed in the cable break every 100 meters. Repeaters can be used to connect network cable several detached buildings.

- router (or router) - a network device that, based on information about the network structure, according to a certain algorithm, selects a route for forwarding packets between different network segments.

Routers are used to combine networks of different types, often incompatible in architecture and protocols (for example, to connect Ethernet to a WAN network). Also, the router is used to provide access from the local network to the global Internet, while performing the functions of a firewall.

A router can be presented not only in hardware, but also in software. Any computer on the network with the appropriate software installed can serve as a router.

Switches:

- D-Link DES-1026G, 24-port fast ethernet switch 10 / 100Mbps, 2-port 10/100 / 1000Mbps;

- D-LinkWebSmartPro switch with 24 10/100 / 1000Base-T ports with PoE (802.3af) support + 4 100 / 1000BASE-T SFP ports and power saving function.

Equipment for Internet connection - DSL-564T ADSL Eth modem Router 4 LAN & 1 ADSL port, IP, Annex B.

- AquariusSrvN70 D11 (211300 / 4D / 1024 / HDD 73 GbU320 SCSISCA 10 krmp).

Cable system:

- Hyperline HF1IA01G5 (FO-ZIP-IN-50-2-FRPVC) Fiber optic cable 50/125 (OM2) multimode internal, zip-cord, 2 cores;

Category 5 unshielded twisted pair UTP;

RJ-45 UTP 5e socket;

3C996-SX GigabitEtherLink, OEM / 1000Base-SX, PCI - For PCs with data transfer rates over 100 Mbps;

3com 10 / 100Mbps-inpack FastEthernetAdapter Rj-45 - For PCs with data transfer rates less than 100 Mbps;

5. Calculating the cost of equipment

5.1 Calculation of the cost of purchased equipment is shown in Table 2.

Table 2 - Calculation of the cost of equipment

Since the physical location of the working groups in buildings is not known, the approximate length of the fiber-optic cable for external installation was calculated based on the fact that the distance between the floors of the building is 10 meters, the cable length for the distance between building 1 and building 2 is about 150 meters.

To calculate the approximate length of the twisted pair for internal installation, the cable length between the working groups was taken as 50 meters. The length of the twisted pair is calculated at the rate of 100 meters for each workgroup.

The approximate cost of the projected local area network is 792,255.4 rubles.

6. Analysis of the information system

6.1 Server hardware

The choice of the network operating system is influenced by the size Money that can be spent on network hardware and software. One of the most powerful and fastest servers for performing any task is the AbsoluteDS 2x5506x5UDualXeonE5506 / 8Gb / 3x600 10KSATAHS-RAID / TS700-E6-RS8 / DVDRW / Pedestal server. Two Xeon processors provide the power you need in any application, and three SATA HDD 600Gb 10000rpm always provide the required speed, capacity and reliability.

Table 3 - Server configuration

6.2 Hardware of workstations

Requirements for computers used as workstations are determined primarily based on the tasks that will be solved on these workstations.

If the workstation is connected to a network, it does not need a hard drive or floppy disks.

The benefits of a diskless workstation are clear. In addition to reducing the cost of the station itself, the risk of virus infection is excluded - there is no floppy disk, and there is no way to bring a virus.

In addition, it provides "hardware" protection of information from unauthorized copying. Users will not be able to copy information from the file server, since there is physically nowhere to write it.

For normal operation, workstations are required with the following minimal set technical characteristics:

RAM 4 GB;

Quad-core processor, frequency from 2.4 GHz;

Disk drive 500 GB;

Operating system Windows 7.

6.3 Software selection

In local networks with a dedicated server, special operating systems are used on the server to ensure reliable and efficient processing of many requests from user workstations.

Workstations of such a local network can use any operating system, for example Windows, etc., and a driver must be running to provide access to the local network.

In networks with a large number of servers, the Windows Server 2008 operating system is often used, as it provides a convenient means for centralized resource management of such networks. Since it is the management of network resources that usually accounts for more than half of the operating costs.

Hardware Windows requirements Server 2008 are shown in Table 4.

Table 4 - Server hardware requirements

In addition to the network OS, for the effective work of users in the local network, other software is required, which sometimes comes with the network OS, and sometimes it must be purchased separately:

- e-mail ensures the delivery of letters (and often arbitrary files, as well as voice and fax messages) from some users of the local network to others, and sometimes allows you to communicate with remote users via modem or via InterNet;

- funds remote access allow you to connect to a local network using a modem and work on a computer as if it were directly connected to the network (of course, many operations will take longer, since the modem is much slower than the network controller);

- means of group work (the most popular of them is Lotus Notes) allow you to work together on documents, ensure the consistency of versions of documents for different users, provide tools for organizing the workflow of an enterprise, allow you to organize teleconferences - written exchange of views on various topics, etc.;

- backup programs allow you to create backup copies of data stored on local network servers and on users' computers, and, if necessary, restore data from their backup;

- Local network management tools allow you to manage the resources of the local network from one workstation, obtain information about the status and load of the network, adjust network performance, manage the systems of network users (for example, install software on them), etc.

6.4 Ensuring the reliability and protection of information

The security of the company's internal network will be ensured by the Internet Control Server (ICS) firewall. Also, with the help of ICS, you can build a secure channel for transferring data between geographically distributed offices, provide access to the network for remote employees.

The reliability of the LAN of the automation object should be ensured on the basis of:

- the use of highly reliable and fault-tolerant equipment;

- making special technological solutions, including redundancy, ensuring high fault tolerance and survivability of the most responsible and vital LAN systems;

- organization of unified operation of all LAN systems;
the use of unified technical means both within the framework of individual systems, subsystems and complexes, and the LAN as a whole;

- the LAN control center must provide diagnostics of system malfunctions and their prevention;

- LAN administrators should receive messages about all failures and switching in systems;

The reliability of cable systems should be ensured by the use of the following technical and organizational solutions:

- backbone connections of active equipment must be duplicated, one of the connections must go through the main SCS backbone, the other through the backup one;

- the materials and equipment used must meet the requirements of regulatory and technical documents for fire resistance and fire safety;

- cables must be laid in hidden places (trays and / or boxes);

- for the implementation of the horizontal subsystem of the SCS, shielded components of a category not lower than 5e must be used;

- to connect computers and other equipment, replaceable, easily replaceable terminal cords should be used.

The system of protection against unauthorized access (NSD) should provide control of access to the network at the level of access to the data transmission medium and to information resources networks:

- LAN equipment, must ensure the protection of information from unauthorized access;

- any attempt of unauthorized access to the network should occur automatic shutdown device ports with immediate administrator notification;

- the network administrator must be able to remotely control access to the network with obtaining information about active users;

- the possibility of interception of packets by users who are not the true recipients of the packets should be minimized;

- access to equipment installed in distribution cabinets must be authorized - cabinets must have lockable doors;

- the protection of information of individual services processing confidential information or information representing state secrets should be ensured;

- access to premises with LAN equipment should be regulated by a regulation developed by the Security Directorate of the Federal Tax Service of Russia and agreed with the Information Technology Directorate on the basis of an access control and management system.

Conclusion

Based on the assignment, a computer network was designed that united 320 workstations and two servers. The network connected 8 college buildings. They implement FastEthernet technology of 10 \ 100 BaseTX specification and GigabitEthernet technology of 10 \ 100 \ 1000 BaseT specification. All workstations in each department are connected to a switch located in the same or adjacent department. In turn, the department switches are connected to the switches of their floor, which are connected to the main switch of the building.

Fiber optic is used to connect buildings to each other. It is possible to expand the network, as the ports of some switches are not fully utilized. For the convenience of cable laying and its structuring, a structured cabling system is used. There is Internet access.

This network is built on the equipment of the companies D-Link, VCOM, Hyperline, Neomax, Absolute, the cost of which was 792,255.4 rubles.

Bibliography

1. Olifer V.G., Olifer N.A. Computer networks. Principles, technologies, protocols. - SPb: Peter, 2012 .-- 944c.

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Composition of local area networks (LAN) of an enterprise (organization), their topology, protocols, distribution of resources and access rights

Basic LAN characteristics:

• * territorial length of the network (length of the general communication channel);
• * maximum data transfer rate;
• * maximum number of speakers in the network;
• * the maximum possible distance between workstations in the network;
• * network topology;
• * type of physical data transmission medium;
• * maximum number of data transmission channels;
• * type of signal transmission (synchronous or asynchronous);
• * method of subscribers access to the network;
• * software structure of the network;
• * the ability to transmit speech and video signals;
• * conditions for reliable network operation;
• * Possibility of LAN communication with each other and with a network of a higher level;
• * the ability to use the prioritization procedure while simultaneously connecting subscribers to a common channel.

The enterprise has 2 local networks. One in the organization, and the other connects all migration services, access by domain, each user has their own password.

Types of local networks.

All modern local area networks are divided into two types:

• Peer-to-peer
• · with centralized management.

In a peer-to-peernetwork, all computers are equal - each of the computers can be both a server and a client. The user of each of the computers decides for himself what resources will be provided in common use and to whom.

In centrally managed networks, the security policy is the same for all users on the network.

An enterprise topology is in the stars - the basic topology of a computer network in which all computers on the network are connected to a central site (usually a switch), forming a physical segment of the network. Such a network segment can function both separately and as part of a complex network topology (usually a "tree"). All information exchange is carried out exclusively through the central computer, on which a very large load is imposed in this way, therefore it cannot be engaged in anything other than the network. As a rule, it is the central computer that is the most powerful, and it is on it that all the functions of managing the exchange are entrusted. In principle, no conflicts in a network with a star topology are possible, because the management is completely centralized.

Organization protocols:

The communication protocols used are IPX / SPX and NETBIOS.

IPX is the underlying protocol in NovellNetWare. It defines the format of packets transmitted over the network and the interface with the network software. At the IPX level, workstations can exchange blocks of data without acknowledgment of receipt.

The SPX protocol assumes that workstations establish communication with each other before starting data exchange. At the SPX protocol level, the delivery of packets transmitted over the network is guaranteed. Packets of information are retransmitted as needed. SPX is based on IPX and is a higher layer protocol.

NETBIOS protocol is designed to transfer data between workstations. It is an even higher level protocol.

Sometimes in local networks you can find the TCP / IP protocol. This protocol is executed on the basis of the UNIX operating system, and is also used to transfer information between computers of the global computer network.

Local area networks of enterprises have been formed for more than 40 years, since the installation of electronic computers (computers), which sometimes occupied the size of an entire room.

The term "local area networks" came to us from the west. In English, it sounds like "Local Area Network".
The Local Area Network (LAN) is the hardware and software used collectively for the task of combining a company's computing resources into a single distributed information processing and storage system. Thus, the installation of a LAN means the creation of a highly functional digital data exchange network.

In addition to computers, other equipment is connected to the LAN: active network equipment, which includes adapters, hubs, switches and routers, network gateways.

TO software include network operating systems, information transfer protocols and network technologies used. The viability of the future local area network depends on the quality of the technologies used.

Currently widely used technologies for creation of local networks are technologies: Asynchronous Transfer Mode (ATM), Gigabit Ethernet and Fast Ethernet (100BaseT). Distinctive feature modern local area networks - high data transfer rate, flexibility, modular architecture.

Virtual Private Network (VPN) technology allows you to combine disparate local area networks into a single corporate network with a high degree of protection and redundancy of communication channels. VPN networks allow companies to avoid using expensive urban communication channels. VPN allows using internal communication channels and the Internet for communications of company employees and data transfer.

The enterprise network infrastructure has the following functionalities:

File transfer - any, even the smallest local area network has the ability to transfer information.
collaboration tools. LAN users have access to shared folders and files for collaboration.
differentiation of employee access rights to the Internet
general use of office equipment.
corporate email. Corporate server capabilities Email depending on the settings, they allow you to receive and send capacious attachments, carry out mass mailings, use the common address book of employees, etc.
information protection is one of the main features of local area networks. The network administrator can impose restrictions on the access rights of employees to the Internet, organize spam filters for incoming corporate mail traffic, exclude entertainment Internet resources, online sales catalogs, social networks to view.

The average organization's LAN is divided into active and passive equipment, as well as computers (and other terminal devices) of users. Active LAN equipment includes:

• network switches (hubs, switches)
• routers
• network cards of servers and personal computers
• points WiFi access
• routers (a device with the functionality of all of the above devices)

Let's consider one of the components of active LAN equipment - switching equipment.

The task of designing a new or modernizing an existing local network of an enterprise is an important issue and requires a serious approach and in-depth study of the details of the operation of the entire system.

Let's consider the main points on the choice of switches for solving the problems of an enterprise LAN network. A switch (aka a hub, aka a switch) is a network device that unites several computers into a local area network (LAN). It is necessary to understand well the logic of work and select sets of parameters and functions that provide the necessary and additional services to users, as well as simplify the administration of the LAN.

Organization of active LAN equipment

The upper switching level is represented by the switches of the network core - Core layer- high-performance devices with ultra-high data transfer rates up to 40Gb, as a rule, are used to exchange data between servers.

The middle layer of the LAN is represented by aggregation switches - Distribution (Agregation) layer- provide network settings in terms of security policies, QoS, VLAN routing, broadcast domains.

And the lower level - workgroup switches or access (user) switches - Access layer- connection of end PCs, laptops and other users, marking of QoS traffic, power supply of PoE devices.

Choosing the right switches will ensure that your entire organization operates reliably and correctly. What points to pay attention to when choosing a switch? Carefully study the technical characteristics and designations in the description given by the manufacturer.

Functional characteristics of switches

The task of the network designer is to find a middle ground and pay an adequate price for maximum functions and high reliability.

The main functions of the switches:

• Base baud rate
• Number of ports.
• The nature of the work of the users connected to it.
• Internal bandwidth.
• Auto detection of MDI / MDI-X cable type.
• Uplink port.
• Stacking.
• Rack mountable.
• Number of expansion slots
• Jumbo Frame - Power over Ethernet (PoE)
• The size of the MAC address table.
• Flow Control
• Built-in lightning protection.

Enterprise LAN router

Router - provides access to information streams between the branch parts of the enterprise LAN and the Internet. On network layer L3 OSI processing of packet routes in the network is assigned to the aggregation routing switches (L3 switches). The second type of router is edge devices - their task is to build packet routes according to recipient and sender addresses and analyze packet routes, monitoring the load of SPD lines. Border routers provide protection against tampering, network segments from broadcast DDOS attacks.

Enterprise LAN Requirements

• speed - essential characteristic local network;
• adaptability - the property of a LAN to expand and install workstations where it is required;
• reliability - the property of a LAN to maintain full or partial operability, regardless of the failure of the terminal equipment or some nodes;
• productivity and efficiency;
• scalability - the ability to easily deploy any IP systems (for example, video surveillance over the current network);
• ease of management and operation;
• fault tolerance, flexibility in configuration and self-tuning during recovery;
• warranty service (maybe for the entire life of the endOFlife product - on average 5-7 years).

For uninterrupted efficient operation of a LAN whose switches need power consumption, it is necessary to provide a guaranteed power supply and emergency power supply in accordance with the governing documents of your industry.

The company "AESTEL" presents to partners only the best devices and solutions. Our experts will help you make your choice, and if necessary, we will design your company's network topology, which will take into account all the requirements for data flows (load, speed, data transmission medium: copper-optics, as well as existing equipment) and wishes.

For examples of calculating various options and topologies of a LAN, see the section.

Organization of passive LAN equipment

Passive network equipment- this equipment does not need electricity consumption and

which does not change the signal at the information level. The main function of passive equipment is to provide signal transmission - these are sockets, connectors, patch panels, cables, patch cords, cable channels, as well as wiring cabinets, racks and telecommunication cabinets. All this equipment is called structured cabling systems (SCS) - has a clear hierarchy in structure, certification international systems standardizations and, accordingly, by types of use, depending on the requirements for objects and the quality of data transmission.