Functions of the local network server. Local area network - what is it and why is it needed? 2 what functions does a local network perform

Do you want to optimize the work of the company as much as possible? You just need to set up a local area network. This will allow employees to use the computer equipment, databases and programs necessary for their work. Regardless of the location of the workplace, team members will be able to transfer information, forward e-mail, etc.

Key Features and Benefits of a LAN

Highlight the main functions of the LAN. It:

• prompt sending of documentation (in electronic form) to all branches of the organization;
• constant communication between the team. LAN will provide communication between employees located in
• head office and branches;
• the ability to access office equipment (printers, faxes, modems) from different points of the office;
• automation of the use of all databases (archives, storages);
• provision of collective access to the Internet;
• remote communication (teleconferences). This is important for meetings, conferences;
• possibility of remote network administration.

Actual LAN installation price available on the website of the company providing such a service. Please read the price list carefully before applying.

After installing the LAN, you get the opportunity to quickly receive and send any information. Plus, by connecting all computers to a single communication network, the speed of work as a whole is significantly increased.

What is LAN installation? The work consists of several stages:

• visit of a specialist to the object;
• system design;
• selection of the necessary equipment;
• direct installation work;
• adjustment and adjustment of equipment;
• testing and delivery.

LAN installation should only be carried out by professionals. This process requires strict adherence to technology. The slightest mistake will lead to the fact that office equipment simply will not function. This is unacceptable downtime for the company and losses.

Firms offering LAN installation must be licensed to engage in such activities. An important factor is the minimum time during which the work will be completed. After the installation is completed, it is wiser to conclude a contract for servicing the system.

After connecting computers to a single network, you will immediately feel the difference. The work will be done much faster. LAN capabilities allow you to connect devices to it in different offices, cities and even countries.

Good day.

In this article, we will analyze what a local network is, why it is needed, how it is organized and what types it happens. Such a network may be useful to you, so do not pass by.

Definition

A local area network is one that unites several computers in a small area. This concept translated into English looks like a Local Area Network, so it is often abbreviated as LAN.

The network can be located within the same apartment, office, computer lab, small organization or its department. By this I mean that usually it does not include many computers and they are not at a great distance from each other.

Let's say you can organize a home network if you have a stationary computer, a laptop, a printer, a couple of mobile gadgets, a smart TV, etc. This option is also convenient, for example, for an enterprise where there are 10-20 computers located on different floors . Or for example / a private house.

Why do you need a local network?

LAN may be needed for:

• Data transfer between devices without the participation of external drives (flash drives, disks, etc.);
• Opening access to the Internet for all network members if it is connected to only one computer;
• Management of portable devices from different computers. For example, within the office from any iron, you can print on one printer;
• Organization of voice and video conferences;
• Network games.

Types of local networks

There are only two of them:

• peer-to-peer network. All participants have equal rights, that is, they independently decide which files to open access to and which ones not. It is used in cases of combining a small number of PCs.
• Server based. Actual option when there are more than 10 computers. Increases network performance. The bottom line is that for storing general information, connecting peripheral devices (scanners, printers, etc.), determining routes for sending information and centrally managing the entire network, one machine is allocated - the server - and all the rest are fed to it.

There are also two ways to build a network: with or without wires. Let's consider each separately.

Wired connection

A twisted pair or optical cable is used, which is connected to a PC. Such devices are in any hardware that is no more than 10-15 years old - they are integrated into the motherboard.

Wired bonding provides the most stable and fastest data transfer. In modern versions, the throughput is 100 Mbps and higher through twisted pair. From 10 Gbps over fiber. For this connection, Ethernet technology is most often used.

When the set of computers is large or it is necessary to distribute the Internet from one server, hubs (switches) can be used. They have several connectors for connecting wires. Their functions include relaying the signal entering one port through other interfaces.

Network structure

There are several topologies for connecting computers by wire:

• Line bus - Serial connection of PCs from one to another.
• Type "star" - all network members are powered by one server.
• Ring - the structure of the connection is clear from the name. In this case, server resources are also distributed among all machines, but if one fails, the others will not work.

• Snowflake is the most flexible topology, because it allows you to connect equipment according to the most convenient principle, usually taking into account its functionality.

Wireless way

This refers to the association by radio waves. The most common option now is this. However, it is also possible to connect via Bluetooth and GPRS. In any case, the speed will be lower than with a wired connection. On average, on Wi-Fi it is 10 Mbps and above.

To create a grid without the participation of wires, it is necessary that the computers have a special module. In modern laptops, it is usually built in, but for PCs, you can buy an external device. You also need a single network gateway (router), to which wired Internet will be connected. And network participants will receive it via radio waves.

How is data transferred?

To organize a local network, it is not enough just to physically connect the machines, you also need to configure it. Their work is controlled by programs. In order for computers to understand each other, a single and understandable language for them is used - a network protocol.

It comes in many forms, but packet protocols are the most widely used. What does it mean? The transmitted data is divided into blocks, which are placed in the packet. It also contains recipient and recipient information. Each computer connects to the network with a certain frequency and checks the passing packets: it takes those that are intended for it.

How does iron understand that this or that packet is addressed to it? Each machine has an IP address that is unique within the same network. It is set during the setup process for Windows or another system that you use.

End of article :).

You are always welcome on my blog.

The term "local network" refers to a communication system that combines several computers within the same room, building or several closely spaced buildings of the same enterprise. Cables, telephone lines, or radio channels can be used to connect computers. Thanks to this association, users: get access to information on all computers connected to the LAN (programs, folders, files); can share modems, printers, scanners […]

The term "local network" refers to a communication system that combines several computers within the same room, building or several closely spaced buildings of the same enterprise. Cables, telephone lines, or radio channels can be used to connect computers. Through this association, users:

• get access to information on all computers connected to the LAN (programs, folders, files);
• can share modems, printers, scanners, and other peripherals.

The main types of local networks

LANs are classified according to various criteria. Consider what local networks are, depending on the presence of a control computer:

1. Peer-to-peer - they are relevant for combining a small number of computers (up to 10) and in cases where increased information protection is not required. At the same time, users have equal access rights to information and independently decide which resources of their computer to share. Such networks are extremely easy to install and operate, but it is problematic to ensure reliable data protection in them.
2. Hierarchical, created on the basis of servers - such LANs provide high performance and reliability of information storage with a large number of users. They have a central computer - a server (one or more) designed for:

• centralized management of the LAN, information exchange and resource allocation;
• connection of all peripheral devices;
• storage of special programs, applications and the main part of the LAN information;
• development of message transfer routes within the network.

Consider what types of local networks are by type of communication:

1. Wired - such LANs use twisted pair, fiber optic or coaxial cable as communication channels. A twisted pair consists of 2 twisted conductors. It has a low bandwidth (up to 1 Mbps), but is resistant to interference. A twisted pair of classes 5, 5e, 6, 6e, 7 has a higher bandwidth (from 100 Mbps). The coaxial cable contains a central conductor and an insulating coating, on which another conductor (screen) is applied on top. It can be foil or braided copper wire. Fiber optic cable provides speeds above 10 Gbps. It contains a thin cylinder of glass, which is coated with a shell with a different refractive index.
2. Wireless - they work with data transmission in the infrared range or over radio channels. Such networks transmit information quickly, but are vulnerable to interference from other sources of the same frequency and unauthorized outside access.

What are the types of LAN topologies?

Classification of local networks according to topology (structure) is carried out according to the type of connection of computers.

The network configuration can be:

1. In the form of a bus - when a cable connects computers in series with each other. Connection and exchange of information is carried out through a single communication channel - the bus. This topology is simple and economical, providing fast information transfer. But when the cable is damaged, problems arise with the entire network, and it is not easy to identify the fault location.
2. In the form of a star - when each machine is connected by a separate cable to a server located in the center of the network, which centrally controls the entire network. Such a structure is more resistant to malfunctions and unauthorized access, does not cause difficulties in determining the location of problems, and provides fast data transfer from workstations to the server. It is widely used when creating a local area network. The disadvantages of this structure are the low data transfer rate between individual workstations and the dependence of the entire network on the characteristics of the server.
3. In the form of a ring - when network machines are connected in series with each other and with the server, or jointly perform server functions. Such schemes are easy to manage and quickly gain access to data, but if a single machine fails or the channel between 2 nodes fails, problems arise in the operation of the entire network. To ensure that the communication channel between other computers is not interrupted, special transitional connections must be used in such networks.
4. Cellular - a structure in which communication lines are established with all nearby machines. In such systems, only workstations that intensively exchange information are directly connected. Machines that are not connected by direct links exchange data using pass-throughs using intermediate computers. This structure is suitable for connecting a large number of machines and is often used when organizing global or large local networks. It is maximally resistant to overloads and failures.
5. Tree-like - is a combination of several topologies (tire-star, star-ring). The base of the LAN tree is at the point where the communication data lines are assembled. Such networks are in demand when it is impossible to organize basic topologies.
6. Mixed (hybrid) - when creating large LANs, arbitrary connections between workstations are often used, but subnets with a typical structure can be distinguished.

Now you know what types of local networks exist, how they differ from each other, what are the advantages and disadvantages of each individual type. To decide on the choice of the LAN that suits you, consult with our experts. You can also entrust us

Answer 4 questions, please help. 1) How does a peer-to-peer local network work? 2) How does a local network with a dedicated

server?

3) What type of local area network is installed in your computer class? What functions does it perform?

4) Find out the names of the network service providers in your area.

1) in what structure of the cycle are the statements of the "body" of the cycle necessarily executed at least once?

2) In the while A do B statement, is B placed in place?
3) How many times the loop will be executed
A:=1;
while A<=5 do
A:=A+1;
4) In the while A do B statement; in place A is placed?
5) What operator in the cycle must be present for its correct completion?
6) In which of the cyclic structures, the statements of the body of the cycle do not need to be enclosed in "operator brackets"?
7)After executing statements
K:=0;S:=0;
while K>10 do
S:=S+K;
K:=K+2;
Ps. It's all Pascal.

Five scouts approached the river, through which lay their further path. The river was deep and there was no bridge across it. At the shore stood a boat with sitting

there are two boys in it. The scouts asked the boys to take them all to the other side. Make an algorithm for the crossing if it is known that the boat can accommodate only one soldier or two boys, but the soldier and the boy can no longer accommodate. How many flights can be done? A trip should be considered as the movement of the boat in one direction.
3. Two Englishmen traveling in the wilds of the Amazon, and two of their guides from a local tribe, are required to cross to the opposite bank of the river. At the disposal of travelers there is a small inflatable boat that can accommodate only two people. The British suspect that their guides are from a tribe of cannibals, and feel safe only when they are alone. How to arrange a safe crossing?
4. Three merchants and three robbers approached the river at the same time. Everyone needed to cross to the other, opposite shore. There was a boat at the shore that could only accommodate two people. The merchants looked timidly at the robbers, as they knew that anything could happen during the crossing. If during the crossing on one or another coast the number of merchants and robbers is the same, then the robbers will not touch the merchants; if the number of robbers exceeds the number of merchants by at least one person, then the robbers will kill the merchants. The merchants faced a difficult task, but it was easily solved by them - everyone moved to the other side and there were no victims. How did the merchants and robbers manage to cross to the other side, and how many round trips did the boat make? A trip should be considered as the movement of the boat in one direction.
5. It was in America. Once an Englishman, a Negro and an Indian came to the river, each with his wife. Everyone had to cross to the other side. They had only one boat at their disposal (and that without a rower), capable of accommodating only two. Having agreed among themselves, the men decided to start the crossing, when it suddenly became clear that not one of the wives wanted to cross in a boat with another man's husband or stay on the shore in a man's company without her husband. The husbands hesitated, but still managed to guess how to fulfill the desire of their wives. How did they manage to cross the river?
6. How can a peasant transport a goat, cabbage, two wolves and a dog in a boat from one bank to another, if it is known that the wolf cannot be left unattended with the goat and the dog, the dog is in a “quarrel” with the goat, and the goat is “not indifferent” to cabbage ? There are only three places on the boat, so you can take no more than two animals or one animal and cabbage with you.

The article will discuss what functions the local network server performs. This is a hardware-software complex, with its help the work of all users' computers is regulated. It is based on a very powerful computer, which has high performance, good optimization, multitasking. It is thanks to this that it is possible to quickly process commands from personal devices of clients.

Features of server hardware

The server must be multi-core, with a high degree of fault tolerance. It should also have a hot-swappable hardware feature. In other words, any part can be replaced without disconnecting the server from the clients and the mains. As for client computers, they are much more likely to require repair due to the failure of any parts.

An operating system is used, a kind of layer necessary for communication between executable programs and hardware.

File Server

It is worth noting that this is one of the most important functions of any server hardware. LANs provide all users with access to stored files on a central PC. In addition, they can manage all directories. For example, any user on the network can access the repository for the necessary documents, reports, projects, spreadsheets, even multimedia.

Scheduled work on a file server can never do without the publication of any documents. And this will significantly reduce the time, as well as speed up the execution of tasks. Any participant can view changes, track the status of document corrections or any reports.

The main feature of such a server is that you can control access to files. Assign shared or personal. This means that all users of client PCs will be able to read and modify any file. If only personal access is allowed, then only a few people can view and modify documents.

terminal server

This is a server that provides computing resources to all its users. As a rule, when using it, it is allowed to run only the licensed software necessary for operation. All users have a client called "desktop protocol" installed on their computers. If the connection to the server is correct, then the user will definitely see all the content on the desktop. Now you are aware of what functions the local network server performs when organizing access to files.

He will also be able to work with all programs remotely, for this only his resources are used, there is no load on the client computer. It is worth noting about the features of working with a client. And it lies in the fact that through the clipboard there is an interception of information coming from the client to the server.

Print server

The functions of this type of server include organizing access to printing devices. Sometimes called a print server, it is necessary so that several workers can use one fax or printer at once. This method assumes that remote printing will be performed on the device. Moreover, this printer is not connected directly to one specific working computer. Here are the functions performed by the LAN server in the case of sharing printers and faxes.

The print server allows you to process multiple workflows at once, provides printing documents from multiple personal computers without significant downtime. It is also worth noting that the installation of all printers in one room will greatly simplify the work in the office. If you know the address, then you just need to select the one you need from the list of public devices.

Database server

It is necessary in order to work with SQL queries that come from a personal computer user to a specific database. With the help of such a server, the safety and integrity of all data is ensured. This tool allows you to work with sections, tables, formulas, reports.

Now you know about databases and what a local area network is. The functions of a computer network in this case are to provide access to specific documents to PC users.

The user, when connecting to the database, uses only the processing power of the server hardware. As an example, we can cite computers with the most common versions of software, such as 1C:Enterprise, Parus-Accounting, etc. On such platforms, you can implement a server that uses a database management system:

1. Oracle Database Server.
2. Microsoft SQL Server.
3. MySQL.
4. informix.
5. firebird.

There are other similar DBMS. But what functions does the LAN server perform besides these? He can play the role of a "postman" who delivers letters from the boss to the workers and back.

Mail server

It is necessary in order to store letters, as well as to exchange information between all users of the local network. Moreover, the functions of such a server include storing all user addresses that are available on the network.

In addition, there is an exchange of correspondence between all participants, you can send reports, participate in the mailing list, and also create calendar projects for any meetings and events. In this case, the server and local stations must be on the same network.

Flaws

And now we need to consider what disadvantages server-based LANs can have:

1. In the event of an emergency stop of the server, there is a very high probability of downtime of the entire network. This usually happens when the integrity of network equipment is compromised.
2. High costs, from a financial point of view, for the acquisition of licensed software and equipment.
3. Setting up all the equipment is quite complicated, so qualified technical personnel is required.

Now you know what functions the LAN server performs. Briefly, we have listed all his duties in the article.