Installation of a computer system: a guide for teapots. How to use the Internet How to use the Internet provider

Qia article assigned the basics of the local dimension, here they will be reviewed by the following topics:

• The concept of a local dimension;
• Vlastuvannya local merezhі;
• Setting for the local dimension;
• Topology of the mesh;
• TCP/IP protocols;
• IP addressing.

The concept of a local dimension

Merezha - a group of computers, one by one, for the help of a special facility that ensures the exchange of information between them. Z'ednannya between two computers can be without middle ( two-to-one contact) or with the help of additional links.

Use a sprat type of merging, and local merging is only one of them. A local line is, in fact, a line that is victorious in one house or a well-placed apartment, such as an apartment, for ensuring interoperability of computers and programs that vicorate in them. Local fencing, like in different houses, can be connected between themselves with the help of satellite channels linking fiber-optic fencing, which allows you to create a global fencing, tobto. merezh, which includes a sprat of local merezh.

The Internet is another butt of the network, as it has long since become all-world and all-weather, which includes hundreds of thousands of different networks and hundreds of millions of computers. Regardless of the fact that you deny access to the Internet for an additional modem, local or global connection, the skin of the Internet is actually a cordial of the Internet. For work on the Internet, the most advanced programs are used, such as Internet browsers, FTP clients, programs for work with e-mail and many others.

A computer connected to a cell is called a work station ( workstation). As a rule, a person works from this computer. Merezha has the same computers, none of them work on them. The stench vikoristovuyutsya like keruyuchi center in the merezhі like hoarding information. Such computers are called servers,
As a computer roztashovani porivnya not far one kind of one and z'ednani for the help of high-width mesh adapters, such meshes are called local. When choosing a local system, computers, as a rule, are stashed in the boundaries of one room, or else in close stashed houses.
For the connection of computers or multiple local networks, as well as distribution of one type of one on a significant station, modems are used, as well as viewing or satellite channels of communication. Such borders sound global. Sound the speed of transmission for such meshes is significantly lower, lower for local ones.

Attachment of local borders

There are two types of architecture of the merezhі: peer-to-peer ( Peer-to-peer) that client/server ( Client/Server), At the moment, the client/server architecture is practically peer-to-peer.

As a peer-to-peer network wins, all computers that enter before it may have the same rights. Obviously, whether a computer can act as a server, which gives access to its resources, or a client, some kind of resource of other servers.

At the edge, pobudovanoї on the architecture of the client / server, є kіlka main computers - servers. Іnshі computers, yakі go to the merezhі, zvієnіv, chi working stations.

Server tse computer, what kind of service computers at the merezhі. Іsnuyut raznomanіtnі see servers, scho vіdznyayutsya one kind of one servants, like a stench; database servers, file servers, print servers, mail servers, web servers, etc.

Peer-to-peer architecture has become more widespread in small offices or in home local areas. In order to create such a network, you will need a couple of computers, how to make a network of cards, and a cable. Like a cable twisted twisted pair of the fourth or fifth category. Wita pair took this name from the fact that the pair was wired in the middle of the cable twisted ( ce allows you to hide the cross code of that ovnіshny infusion). Dosi can be used to finish the old merezhі, like vikoristovuyut coaxial cable. Such networks are morally obsolete, and the speed of transmission from them is selected at 10 Mbit / s.

After that, as the mesh will be created, and the computers are connected among themselves, it is necessary to adjust all the necessary parameters programmatically. First of all, change your mind, what are the computers, what are they getting into, if the operating systems have been installed with the support of the robot in the border ( Linux, FreeBSD, Windows)

All computers in a peer-to-peer network are united with a working group, so that they can make their own names ( identifiers).
In different architectures, the client/server access control system is less dependent on the cores. The administrator has the ability to allow access to the resource to only deakim koristuvachs. Let's assume that you make the printer available for short-term media. If you don't want someone else to work on your printer, then set the password for the robot with this resource. With a peer-to-peer network, be there any kind of koristuvach, some password is recognized, you can take access to your printer. At the client/server level, you can set up a different printer station for certain correspondents independently, even if you don't know the password.

In order to gain access to the resource in the local area, prompted by the client/server architecture, you can enter the username (Login) and the password (Password). Signify that the name of the correspondent is to reveal information, and the password is confidential.

The process of re-verification of the name of the koristuvach is called identification. The process of verifying the validity of the entered password for the name of the koristuvach - authentication. At once, identification and authentication establish the authorization process. Often the term " authentication» - Winning in a wide sense: for the recognition of authentication.

From what has been said, one can add a nevtish vysnovka to someone who has the only advantage of a peer-to-peer architecture - simplicity and low varity. Merezhі client/server will secure more high level of svidkodії and protection.
Dosit often the same server can disable the functions of dekilkoh servers, for example file and web server. Obviously, a large number of functions, like a viconuvatime server, to lay aside for the purpose of that yogo possibilities. The higher the server strain, the more clients you can serve, and the more services you can provide. For this reason, it is practical for the server to be assigned a hard-wired computer with a large amount of memory and a fast processor ( as a rule, for the execution of serious tasks, rich processor systems are used)

Setting for local network

The simplest way for a robotic mesh is enough mesh cards and cable. If you need to make a folding lace, then you need a special tie.

Cable

Computers in the local area are connected for additional cables to transmit signals. The cable that connects the two components and the mesh ( for example, two computers) is called a segment. Cables are classified according to the possible values ​​of the transmission speed and the frequency of faults and pardons. Most often, cables of three main categories are victorious:

• Twisted couple;
• Coaxial cable;
• fiber optic cable,

To inspire local merezh at the same time, the widest vikoristovuetsya twisted couple. In the middle of such a cable, it is made up of two or more pairs of copper wire twisted together. Vіta pair can also be different: UTP ( Unshielded Twisted Pair - unshielded twisted pair) and STP ( Shielded Twisted Pair - shielded twisted pair). Different types of building cables transmit signals to a distance of about 100 m. As a rule, UTP itself is used in local networks. STP may have a braided sheath with a mid-thread thread, as it may have a greater rіven zakhistu and strength, a lower sheath for the UTP cable.

In the STP cable, the skin pair of wires additionally screened ( won scorched by a ball of foil), which protect data, which are transmitted, in the form of foreign transfers. This solution allows you to upgrade high speed transmissions on a larger width, lower at a different cable UTP, Wita pair is connected to the computer for an additional RJ-45 rose ( Registered Jack 45), which is the best RJ-11 telephone socket ( regi-steredjack). Vita pair is designed to secure the operation of the network on the speed of 10100 and 1000 Mbit / s.

coaxial cable it is made up of a copper dart, covered with insulation, which is screened with metal weaves and an outer shell. Signals are transmitted through the central port of the cable, as the data were converted in the front. Such a wire can be both ciliary and rich. To organize a local network, two types of coaxial cable are installed: ThinNet ( thin, 10Base2) and ThickNet ( tovstij, 10Base5). At the moment, local networks based on coaxial cable are practically not trapped.

At the core fiber optic cable optical fibers (light conductors) are known, data on which are transmitted from the sight of light pulses. Electrical signals are not transmitted to the fiber optic cable, so the signal cannot be intercepted, which practically excludes unauthorized access to data. The fiber optic cable is twisted for transporting great communications at the maximum available speed.

The main shortfall of such a cable is its crying: it is easy to screw it up, and you can only install it with the help of a special possession.

Merezhev cards

Merezhevі maps allow connecting a computer and a tethered cable. The Merezheva card transforms the information, as it is recognized for administration, into special packages. The package is a logical sequence of data, up to which it includes a header with address information and information. The header contains the address field, where you can find information about the destination address and the data recognition point, the Merezheva board analyzes the recognition address of the received packet and determines which packet is sent to this computer. As soon as the visa is positive, the board will transfer the package to the operating system. In another case, the package cannot be processed. Special security software allows processing all packets that pass through the border. Such is the possibility of victorious system administrators, if they analyze the work of the merezh, those evil-doers for stealing data, who go through it.

Whether a merezhna card may be an individual address, vbudovanu in її microcircuits. Tsya addresses are called physical, or MAC-address ( Media Access Control - access to the transmission medium).

The order of the day, which is drawn with a lace card, is this.

1. Removing information from the operating system and converting it to electrical signals for further transmission by cable;
2. Removal of electrical signals by cable and their transformation into data, with some building a practical operating system;
3. Appointment, chi appointments data package for this computer;
4. Management of the flow of information that passes between the computer and the mesh.

hub

concentrator (hub) - an attachment, building a computer with a physical mirror-like topology. The concentrator may have a small port, which allows you to connect a number of components. A concentrator, which has less than two ports, is called a bridge. The place is needed for the joining of two elements of the fence.

Merezha at once іz concentrator є " hot tire". Data packets for an hour of transmission through the hub will be delivered to all computers connected to the local network.

There are two types of concentrators.

Passive concentrators. Such attachments strengthen the signal without any front trim.
Active hubs ( rich repeaters). Receive input signals, process them and transmit them to the connected computer.

Commutators

Switches are necessary to organize a large close network between a computer-controller and a terminal computer. In the process of transferring data through the switch, information about the MAC addresses of the computers is recorded in the memory. For additional information, the commutator stores a routing table, in which for the skin computer it is indicated that the next segment of the network is assigned.

When the packets of these wines are removed by the switch, I create a special internal system ( segment) between two of their Ports, with a routing table. Then we force the data packet at the port of the terminal computer, relying on the information described in the packet header.

In this manner, the data is isolated from other ports, which allows computers to exchange information with maximum security, as it is available for the city. If the commutator has less than two ports, it is called a bridge.

The switch has the following capabilities:

• Send a package with data from one computer to the last computer;
• Increase the speed of transmission.

Routers

The router, based on the principle of work, guesses the switch, the prote may have a greater set of functional capabilities, not only the MAC, but also the IP addresses of both computers, which take part in the transmission of data. Transporting information between different segments of the network, routers analyze the packet header and try to find the optimal path for moving this packet. The building's router designates a route to a large segment of the network, vicorist information from the route tables, which allows you to create a global connection to the Internet and a global network.
The routers allow the packet to be delivered by the best route, which allows the transmission of the bandwidth of the great cities. Like a segment of a merezhі revantations, the flow of data on a different path,

Merezha topology

The order of layout and connection of computers and other elements in the merging is called the merging topology. The topology can be matched with the map of the network, on which the working stations are displayed, the servers and the other network are equipped. The selected topology is embedding on the open feasibility of the fence, the protocols of the fence are owned, as they will be blocked, as well as the possibility of a further expansion of the fence.

Physical topology This is a description of what order the physical elements of the border will be brought together. The logical topology determines the routes of data packets passing through the border.

There are five types of mesh topology:

• Hot tire;
• Zirka;
• Kiltse;

Hot tire

In this case, all computers are connected to one cable, which is called the data bus. If so, the package will be accepted by all computers, as it is connected to the third segment of the network.

Shvidkodiya merezhі rich in what counts the number of connections to the main bus computers. There are more such computers, then more practises. In addition, a similar topology can become the cause of various collisions, which is to be blamed if a few computers at once try to transmit information to the measure. Imovirnist appearance of a number of growths due to the increase in the number of connections to the computer bus.

Advantages of the connection between topology and topology hot tire» coming:

• Significant savings in cable;
• Ease of creation and management.

Main shortcomings:

• ymovіrnіst appearance kolіzіy zі zbіlshennyam kompyuterіv і merezі;
• having cut the cable, I brought the silent computers to the point of wiping;
• a low price for the protection of information that is being transmitted. Any computer can take the data that is transmitted through the mesh.

Zirka

With a different mirror-like topology, a leather cable segment, which, if it is connected to a network computer, will be connected to a central switch or a concentrator. All packets will be transported from one computer to another via the same port. It is allowed to use both active and passive concentrators. At the time of rozryvu z'ednannya mizh computer and concentrator reshta merezhі prodzhuvati. If the concentrator is out of tune, then stop pratsyuvati merezha. For the help of a mirror-like structure, you can connect one to one local lines.

Using this topology manually for an hour to search for the most important elements: cable, lace adapters, roses, " Zirka richer handy hot tires» and at the time of adding new outbuildings. The next to pay and those who are responsible for the transfer of 100 and 1000 Mbit / s for the topology. zirka».

Yakscho in the very center stars» Change the concentrator, then it is logical to change the topology to the “head bus”.
Perevagi " stars»:

• ease of creation and management;
• high rіven nadіynostі merezhі;
• high protection of information that is transmitted in the middle of the border ( yakscho near the center of the roztashovaniya commutator).

The main shortfall is the failure of the concentrator to bring all the work to the pinning.

Kiltsev topology

In different loop topologies, all computers in the loop are connected to a single loop cable. Packets pass along the circuit in one straight line through the system of payments connected to the system of computers. The skin computer will send a signal and correct it further along the ring.

For topology representations, the transfer of packets behind the ring is organized by the marker method. The marker is the singing sequence of double rows, which avenge the important data. As soon as a marker is attached to the merging, then the right to correct the information in the merging is claimed. Only one token can be transferred in the middle of the ring.

The computer, which is used to transport the data, takes the marker from the array and corrects the information supplied by the ring. The next computer sends the data to the sender until the packet is not delivered to the addressee. After the return of the addressee, confirmation of the return of the computer-controller, and the rest to create a new marker and turn it to the border.

The advantages of topology are as follows:

• more efficiently, lower at the top of the head іz zagalny tire, more obligatory data are served;
• the skin computer is repeating: I will force the signal before the correction of the attacking machine, which allows you to significantly increase the size of the border;
• the ability to set different priorities for access to the measure; With which computer, whichever is the highest priority, you can trim the token more and transmit more information.

Noodles:

• shave the tread cable to the point of impracticality of all treads;
• An older computer can take the data that is transmitted through the link.

TCP/IP protocols

TCP/IP protocols ( Transmission Control Protocol/Internet Protocol) є the main inter-merge protocols and carry out the transfer of data between merezhami different configurations and technologies. The very family of protocols is based on the transfer of information from the Internet, and from other local networks. The TPC/IP protocol family includes all intermediate protocols between the addenda and the physical level. Zagalna їhnya kіlkіst become kіlka tens.

The main middle ones are:

• Transport protocols: TCP - Transmission Control Protocol ( data transfer control protocol) ta інші - manage the transfer of data between computers;
• Routing protocols: IP - Internet Protocol ( internet protocol) and others - ensure the actual transmission of data, complete the addressing of data, designate the best route to the addressee;
• Merged address support protocols: DNS - Domain Name System ( domain name system) that інші - secures the assignment of the unique address of the computer;
• Application service protocols: FTP - File Transfer Protocol ( file transfer protocol), HTTP - HyperText Transfer Protocol (Hypertext Transfer Protocol), TELNET and others - are used to remove access to various services: transfer files between computers, access to WWW, remote terminal access to the system and in;
• Gateway protocols: EGP - Exterior Gateway Protocol ( old gateway protocol) and others - help to transmit information about routing and information about the country of the city, as well as process data for local networks;
• Post Office Protocol: POP - Post Office Protocol ( protocol to the recipient) - wins for retrieving email lists, SMPT Simple Mail Transfer Protocol ( mail transfer protocol) - vikoristovuєtsya for the strength of postal remembrance.

All main merezhev protocols ( NetBEUI, IPX/SPX and TCPIP) є protocols that are routed. But I have to manually update the TSRIR routing. Other protocols are routed automatically by the operating system.

IP addressing

When using a local network based on the TCP / IP protocol, the skin computer takes a unique IP address, which can be recognized as a DHCP server - a special program installed on one of the computers in the network, or by Windows, or manually.

The DHCP server allows you to randomly distribute IP addresses to computers and assign permanent, static IP addresses to existing computers. Windows needs no such possibilities. Because there is a DHCP server in the pool, then by Windows it’s better not to mess up, by installing the operating system in the array automatically ( dynamic) accepting an IP address. Installing and configuring a DHCP server is outside the scope of this book.

The next step is to indicate that when you choose to recognize the IP address of the DHCP server, or by using Windows to capture the computer in the measure, that operation of recognizing the IP address means a three-time hour, the more, the more the measure. In addition, the computer with a DHCP server is guilty of being switched on first.
How can I manually assign static measures to computers ( postiyni, scho do not change) IP-addresses, then the computers will be zavantazhuvatsya more quickly and again, they will appear in the lace edging. For small sizes, this option is the best, and the most yogo mi can be seen in this division.

To communicate with TCP/IP protocols, the basic IP protocol is used, the shards of vins are involved in moving data packets between computers through networks, using different technologies. The very beginning of the universal characteristics of the IP protocol has become possible for the very foundation of the Internet, which is made up of a great number of various networks.

IP data packets

The IP protocol is the delivery service for the entire family of TCP-iR protocols. Information that needs to be included in other protocols is packed into data packets for the IP protocol, a custom header is added to them, and the packets start their cost more through the mesh

IP addressing system

One of the most important fields in the header of a data packet is the IP address of the source and the owner of the packet. Skin IP-addresses can be unique in that intermediary association, they won't win, after having consumed the package for recognition. It is impossible to find two identical addresses on the entire global Internet network.

IP-addresses, on the vіdm_nu vіd zvichaynoї poshtoї ї ї address, vyklyuchaetsya z digits. Vіn occupies a few standard middles of the computer's memory - 4 bytes. If one byte (Byte) is equal to 8 bits (Bit), then the maximum IP address is 4 x 8 = 32 bits.

The bit is the least possible one to save information. New one can get away with less 0 ( throw off the beat) or 1 ( bit set).

Irrespective of those that IP-addresses can be kept the same time, you can write them in a different way. The format of the IP address entry is set to number system type. If so, one and the same address can look different in a different way:

The double number 10000110 is transformed into a ten with an offensive rank: 128 + 0 + 0 + 0 + 0 + 4 + 2 + 0 \u003d 134.
The best option, from a glance of human readability, is the format of writing an IP address in dotted-decimal notation. This format is composed of several tens numbers, separated by specks. A skin number, called an octet (Octet), is the tenth value of a valid byte in an IP address. An octet is named like this, one byte for a double look is composed of eight bits.

When using dot-decimal notation, writing octets to the IP address of the next mother on the page has the following rules:

• Permissible є more than a whole number;
• Numbers of blame buti in the range of 0 to 255.

Elder bits in the IP address, roztashovani levoruch, indicate the class number of the merger. This marriage is called the identifier of the pdmerezh, but the merge prefix. If the address is recognized in the middle of one dimension, the prefix will always be left unchanged. Vіn identifikuє nalezhnіє IP-address ієї merezhі.

For example, if the IP addresses of the computers in the directory are 192.168.0.1 - 192.168.0.30, then the first two octets indicate the directory identifier - 192.168.0.0, and the next two - the identifiers of the hosts.

Skіlki the same bit victorious for quiet chi and other purposes, to lie down in the class of merezha. If the host number is zero, then the addresses are shown not for one specific computer, but for the entire network as a whole.

Merez classification

There are three main classes of measure: А, В, С.

Globally accepted merging classification is shown in the next table, which shows the largest number of merging interfaces available for connection, such IP addresses are selected for merging interfaces (*), and those are left unchanged (N).

For example, in the widest class C, there can be no more than 254 computers, so for the numbering of the widest interfaces, only one of the youngest byte of the IP address is used. Which byte is given the rightmost octet of the dot-decimal notation.

The blame is legal: why can you connect less than 254 computers to class C, and not 256? On the right, in that some internal IP addresses are recognized for a special quotation, and in itself:

Pro - identifying the very merezh;
255 - wide.

Segmentation mesh

The address space of the middle of the skin line allows for a split on the money for the number of hosts in the suburbs ( Subnets). The process of splitting on the border is called segmentation.

For example, as a class C 192.168.1.0 measure, split into several sub-measures, their address ranges will be attackable:

• 192.168.1.0-192.168.1.63;
• 192.168.1.64-192.168.1.127;
• 192.168.1.128-192.168.1.191;
• 192.168.1.192-192.168.1.255.

In times for the numbering of hosts, not the entire right octet of eight bits is beaten, only 6 younger ones. And the two most significant bits, which are left out, signify the number of the subdivision, which can take the value from zero to three.

Like a great one, so the extensions of the merezhі prefixes can be identified by the help of the mask of the subdivision ( subnet mask), so that it also allows the identification in the IP address of the identifier of the subdivision of the host identifier, masking for an additional number that part of the IP address that identifies the subdivision.

The mask is a combination of numbers that looks like an IP address. A double record of the mask to remove zeros in the digits, which is interpreted as a host number. Others, set to one, point to those that are part of the address with a prefix. The immediacy mask is always set in pair with the IP address.

Due to the presence of the additional distribution on the borders of the mask of the standard classes, the measurements may have the following meanings:

If the victorious mechanism of smashing on the pdmerezhі, the mask is changed to the appropriate order. It is understandable that, vikoristovuyuchi already fortune-telling butt from broken merezhi class C on chotiri pіdmerezhі.

In this case, two older bits in the fourth octet of the IP address are chosen for numbering the subdivision. Then the mask in the double form looks like this: 11111111.11111111.11111111.11000000, and in the dotted-decimal form -255.255.255.192.

Range of address of private measures

Skin computer, connections to the network, send your own unique IP address. For some machines, for example servers, these addresses are not changed. Such a fixed address is called static. For others, for example, clients, IP-addresses can be permanent (static) or recognized dynamically, with a skin connection to a minimum.

In order to take a unique static, to post an IP address in the Internet, it is necessary to return to a special organization InterNIC - Internet Network Information Center ( Merezhevy Internet Information Center). InterNIC assigns only the number of the fence, and the further work of setting up the number of hosts and the numbering of the hosts of the fence is the administrator's responsibility to deal with independently.

Ale official registration in InterNIC with the method of removing static IP-addresses is necessary for merezh, as a permanent connection to the Internet. For private measures, if you do not enter the Internet warehouse, a block of address space is specially reserved, so you can freely, without registering in InterNIC, win for assigning an IP address:

However, these addresses are not used for internal addressing, and are not recognized for hosts, as they connect directly to the Internet.

The range of the LINKLOCAL address is not a class of merezhі with a great understanding. Windows wins when automatically assigning special IP addresses to computers in the local area.

I'm sure you now have a notification about the local border!

How does the Internet work?

The Internet is an international system of computer networks based on IP and routing of IP packets. For a rahunok of a foldable arc of a galvanized system, the Internet allows you to store millions of computers in the whole world. We encourage you to recognize how the Internet works.

Structure of the Internet

In the whole world, in the offices of companies, state institutions, at private booths and apartments, there are computers. Okremimi groups of stench are united at small local networks (from computers to organization to the city). Tі have their own line to be included to the greater merezh - regional, national. The stench is also a part, but only larger ones - continental. Tsі merezhі are interconnected by colossal for the parameters of the undersea transatlantic fiber optic cable. For a piece of clothing, for example, a computer, which is worth in Orly, ties with a computer near Vancouver. Koristuvachi tsikh two PCs via the Internet can communicate one with one.

Moreover, as the Internet is practiced on the international, world-wide level, it can be reached for the account of the global border - the totality of all computers in the world, which are among themselves for the help of the Internet. Rosemary is truly colossal, even if it’s practically the whole planet stalked by a bunch of rare little bits, for geographical, social, political and other reasons, it’s not possible to use a similar resource.

In addition, it is necessary to complete the great lines, which are not connected, but only often made at once with other lines of the light Internet. For example, this is the situation in Pivnichny Korea. In this country, access to the “All-World Pavutin” is granted only with the permission of the authorities, and officials of the highest rank may have the right to a new one. In the middle of the very edge of the country, the internal network under the name "Kwanmen" became accessible to the city dwellers not long ago. The quantity of information and its nature are strictly controlled by the government of the republic.

How to work with the Internet: warehouse elements

Whether it’s a link to the Internet (if we are looking for information, it’s possible to see the site and that in.) - folded lancets of the last ones that are found in the border. Moreover, the skin is such a process of transferring the appearance of clothes to warehouses. Let's briefly chime in on them.

Koristuvach

Otherwise, as an automatic program, it forces you to ask on the Internet to retrieve information.

Computer

Or be it some other way to access the Internet, for example, a phone, a tablet. Without such outbuildings, it is impossible to enter the border.

Internet provider

This is a commercial organization, a company that provides access to the Internet for 8 computers. The skin area of ​​the country has its own providers. With this, all providers of light are divided into 3 great categories.

• The first - tse rulers as a part of the light Internet, as they can sound their fiber optic networks, as stench and transmit traffic (so that the tasks are shared information, as you can take it via the Internet) to the lower group providers.
• Another - all companies of national and regional equals (created by a large number of suddnim krajny). For example, tse Rostelecom.
• The third one is the number of participants in the market, represented by smaller providers in localities and regions.

Finances are mutual, how they signify, zocrema, the amount of traffic taken off between the two groups (and especially between the first and other categories) providers are even more collapsible. Here, the role of economic moments often plays a role, as well as special interests, politics and others.

Browser

This is a client program for working on the Internet, which can be installed either from a disk or via the Internet. The most popular browsers are Google Chrome, Internet Explorer, Mozilla Firefox, Safari, Opera.

Koristuvach can be installed on your PC absolutely no matter what browser, or you can download some programs for your needs. The skin program has its own characteristics, pluses and minuses.

Domain

Let's understand it, it's on the wrong side, as if the zone on the Internet is occupied by another site. Obviously, the skin page on the Internet can have its own unique domain name - the address, for which you can know the site of the merezhі.

Having launched the browser, in the address bar you enter the domain name of the resource you need. After that, the system is sent from the power supply to the Internet provider. The provider is a server of the DNS (Domain Name System) type, which allows you to recode the domain name of the site into an IP address. IP-addresses (Internet Protocol Address) - the same unique address as a zone on the Internet, presented, on the surface as a domain name, in the form of numbers. Before speech, IP-addresses may not be less than the site, but the computers themselves. The IP address is given to the skin PC by the Internet provider, which gives access to the device. You need to work in order to be able to send traffic to the address you need, so that it reaches the skin specific PC, as well as to eliminate problems in the service.

After the IP-address of the site is recoded from the tenth system to the number two (for participation 0 and 1). In this way, the provider, through the server, sends a request about the removal of information from the required koristuvach to the site on the router.

router

Insha I’ll call this attachment - a router. It will ensure the transfer of information through the mesh. It can be said that the router is the cousin of the GPS-navigator, which wins in life. Knowing the distribution of two points (there is a computer on the Internet and a website on the Internet), the router lays the necessary paths between them to ensure the exchange of information.

The transfer of information is carried out from one router to the other to the end point - the server.

Server

An exhausting computer, which can be hacked in the fall in the first sight of such a task:

• Take care of the management of Internet traffic by computers.
• Engaged in recoding domain names to IP addresses.
• Save data. For example, you can have a server with data of correspondence such as electronic mail: incoming and outgoing sheets, sheets in the box and folders with spam, information from address books and in.
• Recognize in your memory information about the different sites of the city, all the data on them. Such servers are called hosting.

Obviously, in our application, the request to the website will be transferred through routers to the source hosting, which collects information about the Internet site, like a joke. The server response will be sent via the gateway (through routers, Internet providers and browser) to the PC.

However, the first result will be displayed on the monitor, for the transmission of information there will be one of the number of ports, like a vicorist PC.

Port

This is a system resource, which is seen as an add-on for communication with other software programs. So, depending on the same IP-address, these other data will then be separated by different ports. So, the main port for sending electronic mail and OKremo - for її otrimannya.

For work with websites, use an okremy port. Vіn analyze otrimana іnformatsiyu and vіdpravlyaє її to the browser. At the result, we see a bad side.

In fact, the entire description of the process takes a few more than a few seconds. You can judge for yourself by trying the site. The page will appear in front of you literally in a couple of minutes after you enter your domain name in the address bar, or, say, enter the request at the window of the browser.

The newest global network is the Internet, which is a set of interconnected networks, which functions as one network. The main channel for communication with the Internet is a series of events organized by the United States for mutual communication of supercomputers in key scientific research laboratories. This channel is called a backbone and supported by the National Science Foundation of the United States (National Science Foundation).

Three hours in the organization of the cob support fence, access to which is less than enough for a small number of special coristuvachiv, the Internet has grown into a fence, which embraces the whole world and gives access to millions of simple coristuvachiv.
For transmission over the Internet, information is broken up by the TCP / IP protocol into packets of the required size. On the way to the point of recognition, the packages pass through different barriers of different rivers. Depending on the routing scheme, which zastosovuetsya, okremі packets can be transferred to the Internet on different routes, and then picked up in the post sequence when they arrive at the point of destination.

In the process of moving a packet from a dzherel to recognition, you can go through a sprinkling of local ties, regional ties, routers, repeaters, hubs, bridges and gateways. Regional borders (midlevel network) - they are just borders, they can exchange information among themselves without connecting to the Internet.

Repeater (repeater) zabіgaє zabіgaє zasannya kolіvіv, polyuyuchi that transmitting far away іnformatsiyu. Xabi z'ednuyut computers in the segment segment, allowing them to interact one by one. The bridges bridge the various borders, allowing you to win the international broadcast of data. A special type of bridge, which is called a gateway, converts messages to exchange between different types of tethers (for example, between Windows tethers and Apple tethers).

Postal workers of the Internet services.

Access to the Internet is reserved for employees and companies provided by companies that provide Internet services (ISP, Internet Service Provide). These companies will block the address of the Internet, which they can recognize to their customers. If the coristuvach is connected to the postmaster of the Internet services, the vin is connected to the server, which has its own line of connections to the Internet for additional outbuildings, which are called routers. The router is an attachment, which accepts a number of packets from the nodes of a number and determines the address recognized on the Internet and the best route for delivering the packet to the given address. Routing is established on the basis of different channels on the Internet and the traffic on different segments. The next router forwards the packet to a network access point (NAP).

The services that the provider of Internet services provides to their clients include:

Zasіb іnternet-identifіkatsії v vglyadі IP-addresses;

E-mail services via POP3 and SMTP servers;

News services via Usenet servers;

Routing through DNS servers.

IP addresses.

Internet service providers give their clients addresses to access the Internet, which are called IP addresses or IP addresses. IP addresses uniquely identify a correspondent on the Internet, allowing him to receive different information. At the same time, two versions of addressing on the Internet are victorious: IPv4 and IPv6.

Until 2000, the most important version was the version of IPv4. In this version of the IP protocol, the skin node of the border has numeric addresses in the form XXX.YYY.ZZZ.AAA, where the group of letters represents a three-digit number in the tenth format (or 8-bit in the two-digit format). This format is called dotted decimal notation, and the group itself is called an octet. The tenth number of the skin octet comes from the two numbers, with which the equipment is safe. For example, the merged address is 10000111. 10001011. 01001001. 00110110 for the two format, the addresses are 135. 139. 073. 054 for the tenth format.

IP-addresses are accumulated from the addresses of the number and the addresses of the node. The addresses of the measure identify the entire measure, and the addresses of the node are the primary node of the measure: the router, the server that works as a station. Local tiers are divided into 3 classes: A, B, C. The affiliation of a tier to the first class is determined by the tier part of the IP address.

The address of the measure A is reserved for great measures. For the local part of the address, the first 8 bits (levoruch) are entered, and the node addresses are the remaining 24 bits of the IP address. The first (highest) bit of the first octet of the link address is 0, followed by a combination of 7 bits. Obviously, class A IP addresses occupy the range 001.х.х.х – 126.х.х.х, which allows addressing 126 okremezh, in the skin of which there will be about 17 million nodes.

Range address 1 27.х.х.х reservations for testing merging systems. Acts z tsikh address be in the order of the United States for testing the basic Internet. The address 127.0.0.1 is reserved for testing the local system bus.

The addresses of the class are assigned to the merezhas of the average size. The value of the first two octets lies in the numerical range 128.x.x.x - 191.254.0.0. Tse allows you to address up to 16,384 different threads, skin from them can mother 65,534 knots.

Addresses to class Z are to be used for merezh, where the number of nodes is small. The merezha part of the address is indicated by the first three octets, and the merezha - by the rest. The values ​​of the first three octets, which represent the same address, may be in the range 192.x.x.x - 223.254.254.0. In this way, class addresses are allowed to address approximately 2 million merezh, skin s of them can mother up to 254 nodes.

The IPv6 version of the IP protocol has been decommissioned to resolve the issue of address mismatch, supported by the IPv4 version. Addresses recognized by IPv6 can be 128 bits or 16 bytes long, which allows you to increase the size of the IP address. The IPv6 protocol also transmits the authentication of the source of the packet, as well as encryption within the packet. Support for the IPv6 protocol introduced in Windows 7 and many Linux distributions; And with the rest of the fates, this protocol is zastosovuetsya more often. The IPv6 protocol secures support for mobile phones, on-board computers in cars and a wide range of other personal devices connected to the Internet.

IPv6 addresses are written in eight groups of fourteen-digit hexadecimal numbers separated by two: 2001:0db8:00a7:0051:4dc1:635b:0000:2ffe. Zero groups can be subverted by two. Ale addresses cannot be more than two consecutive two-fold. For clarity, leading zeros may be omitted. If the URL is different, the IPv6 address needs to be placed in square arches - http://.

Pdmerezhi.

The nodes of the section of the border can be grouped in subdivisions from the upper range of the IP address. Qi groups are called intrameasures. The leather segment of the intramural area can be equipped with a secure gateway, which plays the role of the entry and exit points of the segment. Set the role of the gateway as an attachment, which is called a router. The router is an intelligent device that sends data to the owner's IP address.

At some fences, like a real gateway, a fenced screen or, in other words, a firewall (firewall) is installed. The ultimate firewall is a combination of hardware and software components that create a protective barrier between the security lines with different levels of security. The administrator can adjust the firewall so that it is only possible to pass data on the specified IP address and port.

To create a subdivision, the subdivision part of the node's IP address is masked, so it is necessary to enable it before the immigration. At zv'yazku z tsim, the mobility of data is intermingled by nodes in the middle, shards of these universities can recognize addresses only within the boundaries of a masked range. There are three main reasons for the creation of pidmerezhi.

• To isolate the different segments of the merezhi one from one. Take, for example, a merezh z 1000 computers. Without blocking the segmentation of skin data, 1000 computers pass through the computer screen. Show yourself an interest in making calls. Okrіm tsgogo, kozhen koristuvach merezhі matime access to these other її members.
• To effectively retrieve the IP address. Zastosuvannya 32-bit IP-address declaration allows the exchange of a number of addresses. If you want 126 lace, leather with 17 million knots, maybe a large number, the address is far from sufficient for a light lace scale.
• To allow you to repeat the same IP-addresses of the merezhі. For example, he added the address to class C between two roztashovanimi in different places, allowing him to see half of the real address. In this manner, offenders can win one address of the measure class C.

In order to create an example, it is necessary to block with numbers whether or not all bits of the IP address octet. For example, a mask for values ​​255 blocks the entire octet, and a mask for values ​​254 blocks all but one address per octet. For class A merging, call the mask 255.0.0.0, for class B merging - mask 255.255.0.0, and for class C merging - mask 255.255.255.0. To recognize the address of a measure, it is necessary to perform a bitwise operation of a logical "I" with an IP address and a mask. For Windows 2000/XP, the value for locking the mask is entered automatically at the hour of entering the IP address.

In contact with

Let's go ahead, let's figure it out, how to practice the Internet.

All computers in the Internet can roughly be divided into two groups - servers and clients.

Servers - all the harder, more expensive computers that work well. The stench is permanently connected to the Internet, saving and transferring information to the power of other computers, powering tens and hundreds of requests at once.

Clients are personal computers that correspond to the Internet, on which it is possible to store and download power to servers, and to display and display information. Often the computer does not connect to the Internet permanently, but is connected when necessary.

For connecting to the Internet, we apply to the services of special organizations - providers of services to the Internet.

Internet provider- the whole organization that gives access to the Internet through its own Internet server. Corylist computers (clients) are connected to the provider's server by telephone lines, a visible channel or a wireless network. I have my own server and provider connected with the Internet with permanent high-speed lines.

On the computers of the correspondents of the Internet, there is a separate software security, for example, a browser, which stores and powers up the server, then removes that information on the monitor screen. On the server, on its own side, it has its own software security installed, as it saves information and confirms it on the request of the client's software security.

And now it should be noted that different types of computers may have different types of computers, which have different operating systems installed (Windows, Vista or so), browsers (Opera, Internet Explorer, Mozilla Firefox). Different types of computers and different server software are also installed on different servers. In order for programs written by different authors for different types of computers, with different operating systems, to be able to interact correctly with each other, special rules were invented - Protocols. You can boldly say that protocols help computers exchange information.

For Internet skin service, use your own application protocol. For example, if you want to send an e-mail, then your computer may have the program installed, and the server has its own program that supports your program application level protocol, which ensures the interaction between the client program and the server.

In this rank, for the sake of serving the Internet, we need:

• Computer
• The client program, installed on our computer, is designed to work with the service protocol
• Addresses of the server on which the server program is installed.

To make it easier to understand, to put in more information, let's say that the Russian Ivan vyrivishiv posplkuvatisya with the American Bil. For whom Ivan needs to know the English language. And not just to know English words, but to be able to arrange them in the required order, according to the rules (protocols), only the same Bil could understand Vanya.

Only a few words were left, but how did Vanya know Bila, to talk to him? Elementary - Vanya knows Bil's mobile phone number.

One million computers on the Internet know behind this very principle. A leather computer, connecting to the Internet, has its own unique IP address (Internet Protocol Address), as a sequence of several numbers separated by dots, for example 195.5.46.34. The skin number can lie in the range from 0 to 255. IP addresses for a computer, like for us the number of a style phone. In a new way, you can know a computer in a little bit of light.

Dali blame the coming food - as all websites, web sites, blogs are just a part of the all-world database of WWW data, then de and on what polices is it all purpose to lie? And how does our computer get to?

As a rule, sites are hosted on Internet servers, because the servers themselves have a large disk space, the need for software security and the ability to receive tens and hundreds of drinks at once. In order to host a site on the Internet, or rather, at the all-world WWW, you need to go back to the host provider.

Host provider- tse organization that provides services to hosting, tobto. give disk space on the Internet server (Hosting) for placing your site on the Internet. Remember that hosting is not a process of publishing a site, but rather renting disk space.

From the English "host" is translated, like the head computer or the master of the foreign yard. So from, on the other side of the door and call the site. There are thousands of such zazhdzhih yards.

Also, in order to know the site of the all-worldly web, you need to know the IP address of that server where the site is hosted. Like for a computer, to remember a few dozen IP-addresses like a set of numbers, it doesn't matter, then people are smarter.

For ease of roboti Bulo Vigadano Domain name system(DNS - Domain Name System). Tsya alternative addressing system, zrozumіlіsha people, tk. computers are assigned not only IP addresses, but also symbolic names or domain name . The domain name is composed of a lanyard of symbols, divided between them in a speck.

As if domain names weren’t good for a coristuvach, but the robot of all computers was sent to digital addresses, the DNS-server service was created to ensure communication between people and that machine.

DNS server - a program that converts a domain address to a digital IP address and navpacki. So, if you type a domain name in a browser, DNS will calculate which IP addresses you need to give the name and which resource you need to give.

Maybe the DNS server can be matched with the address book in our style phone. We are physically unable to remember all the numbers of the telephones we need, so the number is recorded in the telephone book under unique names. To get on the phone, we know we need a name, and the phone itself picks up, what number to dial, like a DNS server.

Since the server addresses are bigger and smaller, everyone understood, then how do we know and transfer the necessary documents to us on the sites?

World Wide Web WWW inhabited by millions of different documents, which lie on different servers and our task is to know and read the document we need. But for whom our browser can know for sure local knowledge required document.

To all computers, send to dummies, I know well the full name of the file, like including a short file name with extensions and new paths to the file, starting from the name, I will add a disk, then I will redirect the folders, the divisions between the slash "\ ". In this way, we uniquely identify the file at the boundaries of one computer.

A skinned file on the Internet also has its own unique address. Vin is called URL.

URL (Uniform Resource Locator) – a universal resource locator, or the address of any file on the Internet. The computer address in the URL contains a statement about the protocol, how to get to the file, how to run the program on the server, and how to find the particular file.

A typical URL is made up of three main elements: Protocol + Domain Name + Way/File.

Let's take a look at the upcoming URL http://nic.ru/dns/service/dns-service.html. Tsya addresses belong to one of the sides of the RU-Center website.

1. http - this is the protocol, which defines the set of rules, which are used in the interaction between the client and the server. The protocol that accepts WWW transfer to hypertext is called HyperText Transfer Protocol, short for HTTP.
2. Give the domain name of the server, to what extent you are asking for information, our price is nic. ru. De. ru is the top level domain, nic . ru is the domain of another equal. Mіzh domain and protocol should be set to rozdіlnik :// .
3. /dns/service/dns-service.html - the path to the file dns-service.html that we need, which is in the service folder, as it is included in the dns folder.

From i all. In “three words”, I tried to explain to you how the Internet works, that is the most popular resource - the all-world way of the WWW.

Good afternoon, I'm new to merging technologies, so it's hard to judge, it became clunky, like an Internet provider and why do different providers work differently, as if the food was already bulo, then I'll ask again.

Two providers, one works on GPON, ONT can stand in a booth on the mountain, a couple is twisted to the subscribers or at the subscriber's home, like a gigabit tariff, there are dynamic ip addresses by dhcp, there is no binding for a mac-address. If the subscriber has his own VLAN client-VLAN, and the ONT has his own VLAN, then QinQ works.
And another provider via ethernet, subscribers from one or more switches can be in one lan, behind a territorial sign, with a sіrі ip address also via dhcp, with binding to a mac-address and from iptv via multicast.

1. What are the guests/international standards on how the provider can induce merezh chi want to work smart lads and how work is not necessary? Chi varto for skin subscriber robit and okremy lan or unite groups of subscribers at wide domain? What are the pluses and minuses for the skin method for the provider and for the subscriber?
2. In what way should one choose to lay a foundation on a physical and logical level?
3. What is connected with the type of cable? Or is it possible for optics to work, so that subscribers are in the same wide-range domain (for example, from one area), and t, how to twist the pair on the other hand for skin okremia vlan?
4. The first provider has a dynamic IP address, which is the pool, which you have seen for subscribers and the client, which is the right time? another provider has the same address in the pool ip chi all go under one and the same? Why is it due to this, that the other one simply ran out of ip addresses through a larger number of coristuvachiv and the first provider of the same for NAT translation, if the client becomes rich? How great providers win IP range, dynamic IP or nat
5. Shodo iptv. I have a router at home with dns and google, a new cable to Smart TV and the provider can have a program for review. The problem was that I didn’t have a list of channels and it didn’t work, that I put dns on the router as a provider, as explained in the TP, it was connected with it, so that’s how I have a sysym If you didn't give the address to any of the subscribers, then the list is empty. Can you still see the NAS address for the subscriber? it’s just a shovische, marennya chi nі? having checked your IP on the site and having asked a friend who is connected to the same provider for my booth, check it. we have different ip. mean tekhpidtrimka Breshe? (this is a different provider, but with a static ip everything would work, but if not, what is wrong with the sіrimi ip)