To transmit information over communication channels, it is necessary to convert computer signals into signals from physical media.
For example, when transmitting information via a fiber-optic cable, the data presented in the computer will be converted into optical signals, for which special technical devices are used - network adapters.
Network adapters (network cards) - technical devices, you performing functions of pairing computers with communication channels.
Network adapters must match the communication channels. Each type of channel requires its own type of network adapter. The adapter is inserted into an empty socket motherboard computer and connect it with a cable to the network adapter of another computer. On network cards ah set the addresses of computers on the network, without which transmission is impossible. When information circulates over the network, any network computer selects from it only that which is intended specifically for it. It is determined in accordance with the computer address.
Connectors (connectors ) for connecting cables to a computer; connectors for connecting cable sections.
Transceivers increase the quality level of data transmission over the cable, are responsible for receiving signals from the network and detecting conflicts.
Hubs (hubs) And switching hubs (switches) expand the topological, functional and speed capabilities of computer networks. A hub with a set of different types of ports allows combine network segments with different cable systems . You can connect either a separate network node or another hub or cable segment to the hub port.
Repeaters (repeaters) enhance the signals transmitted along the cable over a long cable length.
To connect local networks, the following devices are used, which differ in purpose and capabilities:
Bridge (English Bridge) - connects two local networks. Transfers data between networks in packet form without making any changes to it. The figure below shows three local networks connected by two bridges.
Here, bridges have created an expanded network that provides its users with access to previously inaccessible resources. In addition, bridges can filter packets, protecting the entire network from local data flows and allowing only data destined for other network segments to pass through.
Router (English Router) connects networks with a common protocol more efficiently than a bridge. It allows, for example, large messages to be split into smaller pieces, thereby ensuring the interaction of local networks with different packet sizes.
A router can forward packets to a specific address (bridges only filter out unnecessary packets), choose the best path for the packet to take, and much more. The more complex and larger the network, the greater the benefits of using routers.
Bridge router A Brouter is a hybrid between a bridge and a router that first attempts routing where possible and then switches to bridge mode if that fails.
Gateway (English GateWay), unlike a bridge, is used in cases where the connected networks have different network protocols. A message from one network arriving at the gateway is converted into another message that meets the requirements of the next network. Thus, gateways do not simply connect networks, but allow them to operate as a single network. With the help of gateways, local networks are also connected to mainframes - universal, powerful computers.
Tasks local network: File division. The network allows many users to work on one file at the same time. File separation. The network allows many users to work on one file at the same time. File transfer. The network allows you to quickly copy files of any size from one machine to another without using magnetic media. File transfer. The network allows you to quickly copy files of any size from one machine to another without using magnetic media. Separation application programs. The network allows different users to use the same copy of a program. Separation of application programs. The network allows different users to use the same copy of a program. Printer separation. A network allows multiple users to share one or more printers. Printer separation. A network allows multiple users to share one or more printers. Email. The network allows you to install a mail service to send messages, reports, and memos to other network users. Email. The network allows you to install a mail service to send messages, reports, and memos to other network users. It is fashionable to install on a local network basis software, which makes it possible to use technology global network Internet in the preparation, publication, and use of documents. It is possible to install software on the basis of a local network, which makes it possible to use global Internet technologies when preparing, publishing, and using documents.
Peer-to-peer local network In a peer-to-peer local network, all computers have equal rights. Shared devices can be connected to any computer on the network. In a peer-to-peer local network, all computers have equal rights. Shared devices can be connected to any computer on the network.
Network with a dedicated server Server (from the English server - service device) is a computer that distributes resources between network users. Installed on the server powerful processor, large operational and disk memory, stores the bulk of the network software and data that can be used by all network users. Less powerful computers with less disk and RAM memory are usually used as workstations.
Local network topology The simplest type of topology is bus. In such a network, all computers are connected to one cable. The structure called a ring is also similar to a tire. For local networks based on a file server, the star scheme can be used. The composition of the equipment and software depends on the scheme. The topology is chosen based on the needs of the enterprise. If an enterprise occupies a multi-story building, then it can use a snowflake scheme, in which there are file servers for different workgroups and one central server for the entire enterprise.
Local network equipment: cables for information transmission; cables for information transmission; connectors for connecting cables; connectors for connecting cables; matching terminators; matching terminators; network adapters; network adapters; repeaters; repeaters; transceivers; transceivers; concentrators; concentrators; bridges; bridges; routers; routers; gateways. gateways.
Network adapters (aka controllers, cards, boards, interfaces, NIC Network Interface Card) are the main part of the local network equipment, without which the network is impossible. The purpose of a network adapter is to connect a computer (or other subscriber) to the network, that is, to ensure the exchange of information between the computer and the communication channel in accordance with accepted exchange rules.
Repeaters, or repeaters, perform a simpler function than transceivers. They do not convert signal levels or their appearance, but only restore weakened signals (their amplitude and shape), bringing their shape to its original form. The purpose of this signal relay is to increase the length of the network.
Bridges, routers and gateways are used to combine single network several heterogeneous networks with different lower-level exchange protocols, in particular, with different packet formats, different coding methods, at different speeds transmissions, etc.
Network software To work on a local network, you need special network software. To work on a local network, you need special network software. In the operating room Windows system you already have everything you need to install the network.
Network software To organize a local network you need to: determine the name of the Working Group; assign each computer a unique name and IP address in this Workgroup, and also set a subnet mask address (in some cases, an explicit IP address and subnet mask address may not be set).
Local area network is a concept that is familiar to many firsthand. Almost every enterprise uses this technology, so it can be said that every person has come across it in one way or another. Local networks have significantly accelerated production processes, thereby giving a sharp boost to their further use throughout the globe. All this allows us to predict the further growth and development of such a data transmission system, up to the introduction of a LAN in every, even the smallest enterprise.
The concept of a local network
A local area network is a number of computers connected to each other by special equipment that allows for the full exchange of information between them. An important feature of this type of data transmission is the relatively small area where communication nodes, that is, the computers themselves, are located.
Local networks not only greatly facilitate interaction between users, but also perform some other functions:
- Simplify work with documentation. Employees can edit and view files at their workplace. At the same time, there is no need for collective meetings and meetings, which saves valuable time.
- They allow you to work on documents together with colleagues, when everyone is at their own computer.
- They allow access to applications installed on the server, which allows you to save free space on the installed hard drive.
- Save hard drive space by allowing you to save documents on your host computer.
Types of networks
A local area network can be represented by two models: a peer-to-peer network and a hierarchical one. They differ in the ways communication nodes interact.
A peer-to-peer network is based on the equality of all machines, and data is distributed between each of them. Essentially, a user of one computer can access the resources and information of another. The efficiency of the peer-to-peer model directly depends on the number of worker nodes, and its level of security is unsatisfactory, which, coupled with a rather complex management process, makes such networks not very reliable and convenient.
The hierarchical model includes one (or more) main server, where all data is stored and processed, and several client nodes. This type of network is used much more often than the first, having the advantage of speed, reliability and security. However, the speed of such a LAN largely depends on the server, which under certain conditions can be considered a disadvantage.
Drawing up technical requirements
Local design computer network is a rather complex process. It begins with the development of a technical specification, which should be carefully considered, since shortcomings in it threaten subsequent difficulties in building a network and additional financial costs. Primary design can be done using special configurators that will allow you to select the optimal network equipment. Such programs are especially convenient in that you can correct various values and parameters directly during operation, as well as generate a report at the end of the process. Only after these steps can you proceed to the next stage.
Schematic design
This stage consists of collecting data about the enterprise where it is planned to install a local area network, and analyzing the information received. The quantity is determined:
- Users.
- Workstations.
- Server rooms.
- Connection ports.
An important point is the availability of data on the routes for laying highways and the planning of a specific topology. In general, it is necessary to adhere to a number of requirements imposed by the IEEE 802.3 standard. However, despite these rules, sometimes it may be necessary to make calculations of signal propagation delays or consult with network equipment manufacturers.
Basic LAN characteristics
When choosing a method for placing communication nodes, you must remember the basic requirements for local networks:
- Productivity, which combines several concepts: throughput, reaction time, transmission delay.
- Compatibility, i.e. ability to connect various local area network equipment and software.
- Safety, reliability, i.e. capabilities to prevent unauthorized access and full protection data.
- Scalability - the ability to increase the number of workstations without degrading network performance.
- Manageability - the ability to control the main elements of the network, prevent and eliminate problems.
- Network transparency, which consists of presenting a single computing device to users.
Basic local area network topologies: advantages and disadvantages
The topology of a network represents its physical layout, significantly affecting its basic characteristics. In modern enterprises, three types of topologies are mainly used: “Star”, “Bus” and “Ring”.
The “Star” topology is the most common and has many advantages over others. This installation method is highly reliable; If any computer fails (except the server), this will not affect the operation of the others.
The “Bus” topology is a single backbone cable with connected computers. Such an organization of a local area network saves money, but is not suitable for connecting a large number of computers.
The “Ring” topology is characterized by low reliability due to the special arrangement of nodes - each of them is connected to two others using network cards. The failure of one computer leads to the shutdown of the entire network, so this type of topology is used less and less.
Detailed network design
An enterprise local area network also includes various technologies, equipment and cables. Therefore, the next step will be the selection of all these elements. Making a decision in favor of one or another software or hardware is determined by the purpose of creating the network, the number of users, the list of programs used, the size of the network, and its location. Currently, fiber optic highways are most often used, which are distinguished by their high reliability, speed and availability.
About cable types
Cables are used in networks to transmit signals between workstations; each of them has its own characteristics, which must be taken into account when designing a LAN.
- A twisted pair consists of several pairs of conductors covered with insulation and twisted together. Low price and ease of installation are beneficial advantages, which makes this cable the most popular for installing local networks.
- A coaxial cable consists of two conductors inserted one inside the other. A local area network using coax is no longer so common - it was replaced by twisted pair, but it is still found in some places.
- Optical fiber is a glass thread that can carry light by reflecting it off walls. A cable made from this material transmits data over long distances and is fast compared to twisted pair and coaxial cables, but it is not cheap.
Necessary equipment
Network equipment of local area networks includes many elements, the most commonly used of which are:
- Hub or hub. It connects a number of devices into one segment using a cable.
- Switch. Uses special processors for each port, processing packets separately from other ports, due to which they have high performance.
- Router. This is a device that makes decisions about sending packets based on data about routing tables and some rules.
- Modem. Widely used in communication systems, providing contact with other workstations via cable or telephone network.
End network equipment
Hardware local area network necessarily includes server and client parts.
The server is powerful computer, having high network significance. Its functions include storing information, databases, serving users and processing program codes. The servers are located in special rooms with a controlled constant air temperature - server rooms, and their housing is equipped with additional protection from dust, accidental shutdown, as well as a powerful cooling system. As a rule, only system administrators or company managers.
The workstation is a regular computer connected to the network, that is, it is any computer requesting services from the main server. To ensure communication at such nodes, a modem is used and network card. Since workstations usually use server resources, the client part is equipped with weak memory sticks and small hard drives.
Software
Local area network equipment will not be able to fully perform its functions without suitable software. The software part includes:
- Network operating systems on servers that form the basis of any network. It is the OS that controls access to all network resources, coordinates packet routing, resolves device conflicts. Such systems have built-in support for the TCP/IP, NetBEUI, IPX/SPX protocols.
- Autonomous operating systems that manage the client side. They are common operating systems, for example, Windows XP, Windows 7.
- Network services and applications. These software elements allow to produce various actions: View remote documentation, print to network printer, sending mail messages. Traditional services HTTP, POP-3, SMTP, FTP and Telnet are the basis of this category and are implemented using software.
Nuances of designing local networks
Designing a local area network requires a long and leisurely analysis, as well as taking into account all the subtleties. It is important to provide for the possibility of enterprise growth, which will entail an increase in the scale of the local network. The project must be drawn up in such a way that the LAN is ready at any time to connect a new workstation or other device, as well as upgrade any of its nodes and components.
Security issues are no less important. The cables used to build the network must be reliably protected from unauthorized access, and the lines must be located away from potentially dangerous places where they can be damaged - accidentally or intentionally. LAN components located outside the premises must be grounded and securely secured.
Developing a local area network is a fairly labor-intensive process, but with the right approach and due responsibility, the LAN will operate reliably and stably, ensuring uninterrupted user experience.
constitute active devices that ensure the transfer of information between network nodes. The list of such devices includes network adapters, network hubs and switches, bridges and routers.The network adapter is installed on the network node and connects it to the data transmission channel. To communicate with other network nodes, it performs the following operations: data buffering, packet formation, access to the transmission medium, data conversion, encoding and decoding, and, finally, transmission and reception.
The purpose of network hubs and switches is similar - connecting several LAN nodes lying within the same segment. The difference is that a hub broadcasts traffic from one node to all available nodes, while a switch broadcasts traffic directly to the recipient node. This or that LAN hardware can be selected depending, first of all, on the information load of the network and the requirements for data transmission security. In networks whose nodes are not critical to traffic volumes, hubs are sufficient. Networks that place increased demands on performance and data security must be equipped with switches that eliminate the need and ability of network nodes to process information not intended for them.
Bridges and routers are LAN hardware, providing communication between network segments. Routers, unlike bridges operating at the data link layer - the second in the OSI model, use the third layer of the model - the network. This allows you to transmit packets taking into account the specifics of protocols, select the optimal route for transmitting a packet based on an analysis of information received from other routers about the topology and state of the network. The bridge is transparent to everyone network protocols and, like switches, decides whether to broadcast a packet based solely on the recipient's MAC address.
Related articles:
Structural is a graphic document depicting the physical location and connection components sks.
You should trust only qualified specialists officially approved to work in electrical installations.
As you probably already guessed, from hardware you will need network adapters to connect the computer to the cable, connectors, the cable itself, and, possibly, a device for connecting computers when using a star topology.
Depending on the network topology, the composition of network equipment may vary.
In any case, you will need a network adapter for each computer on the network. This adapter is inserted into the computer's main board (motherboard) and has one or two connectors for connecting to a network cable (of course, a network of computers, not a power supply or lighting network).
There are networks that do not require special adapters - network cable connects to the RS-232-C serial port. These networks are low-performance and are suitable for solving only simple tasks, such as sharing a printer. We will not pay much attention to such networks.
What should owners of laptop computers like Lap-Top and Note Book that do not have expansion slots for connecting network adapters do? Some companies produce Ethernet adapters specifically for such computers in the form of a small box that connects to the printer or serial port of the computer.
As for the cable, coaxial cable or twisted pair (regular telephone wire) is usually used. In critical cases, when it is necessary to connect computers located in different buildings or there are requirements to ensure the protection of information from unauthorized access, fiber-optic cable is used. By the way, the fiber optic cable itself is no more expensive than the coaxial cable, which, however, cannot be said about adapters and other equipment for connecting such a cable.
If you are using coaxial cable, it should not be too long. When the length of the local network is hundreds of meters, it may be necessary to install a special device - a repeater - into the middle of the cable. The repeater's task is not limited to simply amplifying the signal. But we'll talk about this later.
Let's look at the hardware needed to implement the most common access methods - Ethernet, Arcnet and Token-Ring.
2.1. Ethernet hardware
Ethernet hardware typically consists of cable, connectors, T-connectors, terminators, and network adapters.
The cable is obviously used to transfer data between workstations. Connectors are used to connect the cable. These connectors through
T-connectors are connected to network adapters - special cards that are inserted into the expansion slots of the workstation motherboard. Terminators are connected to the open ends of the network. Soon we will tell you more about Ethernet hardware and the purpose of the devices listed above.
There are different types of cables that can be used for Ethernet: thin coaxial cable, thick coaxial cable, and unshielded twisted pair cable. Each type of cable uses its own connectors and its own method of connecting the cable to the network adapter.
Depending on the cable, network characteristics such as the maximum cable length and the maximum number of workstations connected to the cable change.
Typically, the data transfer rate of an Ethernet network reaches 10 Mbits per second, which is sufficient for many applications.
Let's take a closer look at the composition of Ethernet hardware for various types cable.
2.1.1. Thick coaxial cable
The thick coaxial cable used by Ethernet has a diameter of 0.4 inches and a characteristic impedance of 50 ohms. This cable is sometimes called the "yellow cable". This is the most expensive cable we've reviewed. The IEEE Institute has defined the specification for this cable - 10BASE5.
In Fig. Figure 4 schematically shows a local network based on a thick coaxial cable.
Rice. 4. Ethernet on thick coaxial cable
Here is a network configuration consisting of two segments separated by a repeater. Each segment contains three workstations.
Each workstation through network adapter(installed on the computer motherboard and not shown in the figure) is connected to a device called a transceiver using a special multi-core transceiver cable. The transceiver is used to connect the workstation to a thick coaxial cable.
There are three connectors on the transceiver body: two for connecting a thick coaxial cable, and one for connecting a transceiver cable.
In table Table 2 lists the devices needed to connect a workstation to a thick coaxial cable.
Table 2. Hardware for connecting a workstation to a thick coaxial Ethernet cable
Unfortunately, the length of one segment is limited and for a thick cable cannot exceed 500 meters. If the total length of the network is more than 500 meters, it must be divided into segments connected to each other through a special device - a repeater.
Our figure shows two segments connected by a repeater. In this case, the total length of the network can reach one kilometer.
The transceivers are connected to each other by sections of thick coaxial cable with coaxial connectors soldered to their ends.
At the ends of the segment, special plugs are connected - terminators. These are simply coaxial connectors with a 50 ohm resistor installed in the housing.
The housing of one of the terminators must be grounded. Please note that only one terminator can be grounded in each network segment.
Are there any other restrictions besides the maximum segment length? Alas, they do exist (see Table 3).
Table 3. Limits for Ethernet on Thick Cable
In addition to the limitation on the segment length, there are restrictions on the maximum number of segments in the network (and, as a result, the maximum length of the network), on the maximum number of workstations connected to the network, and on the length of the transceiver cable.
However, in most cases these restrictions are not significant. Moreover, the capabilities of a thick cable are often redundant. You can save a lot of money if you make a network based on thin cable, since in this case you will not need any transceivers or transceiver cables. And a thin network cable is cheaper than a thick one.
In Fig. Figure 5 shows the equipment needed for Ethernet networks on a thick cable.
Rice. 5. Ethernet equipment for thick cable
2.1.2. Thin coaxial cable
The thin coaxial cable used for Ethernet has a diameter of 0.2 inches and a characteristic impedance of 50 ohms. The imported cable is called RG-58A/U and complies with the 10BASE2 specification. You can also use the RK-50 cable produced by our industry.
An Ethernet network on a thin cable is much simpler than on a thick one (Fig. 6).
Rice. 6. Ethernet on thin coaxial cable
As a rule, all network adapters have two connectors. One of them is designed for connecting a multi-core transceiver cable, the second is for connecting a small tee called a T-connector.
On one side, the T-connector is connected to the network adapter, and on the other two sides, pieces of thin coaxial cable with corresponding connectors at the ends are connected to it. In this case, it turns out that the coaxial cable is connected directly to the network adapter, so a transceiver and transceiver cable are not needed.
At the ends of the segment there must be terminators that are connected to the free ends of the T-connectors. One (and only one!) terminator in a segment must be grounded.
Networks based on thin cable have worse parameters compared to networks based on thick cable (Table 4). But the cost of the network equipment necessary to create a network on a thin cable is significantly less.
It should be noted that some companies produce Ethernet adapters that can operate with a segment length of up to 300 meters (for example, adapters from 3COM). However, such adapters are more expensive and the entire network in this case must be made using only one type of adapter. To decide whether to purchase more expensive adapters, compare the additional cost to the cost of the repeater that will be needed to achieve the total network length required.
Table 4. Limitations for Ethernet on Thin Cable
As a rule, most Ethernet networks are created on the basis of a thin cable. In Fig. Figure 7 shows the equipment needed for a thin cable Ethernet network.
Rice. 7. Ethernet equipment for thin cable
2.1.3. Unshielded twisted pair
Some (but not all) Ethernet network adapters are capable of operating with a cable that is a simple unshielded twisted pair of wires (10BASE-T specification). As such a cable, you can use a regular telephone wire and the telephone network that already exists in your organization.
Network adapters capable of working with twisted pair cables have a connector similar to that used in imported telephone sets.
For an Ethernet network based on twisted pair, a special device is required - a hub. Up to 12 workstations can be connected to one hub via the same telephone sockets. The maximum distance from the hub to the workstation is 100 meters. In this case, the data transfer speed is the same as for coaxial cable - 10 Mbit per second.
The advantages of a network based on twisted pair are obvious - low cost of equipment and the ability to use the existing telephone network. However, there are serious restrictions on the number of stations in the network and on its length.
2.1.4. Ethernet network adapter
Regardless of the cable you use, you will need to purchase a network adapter for each workstation. A network adapter is a card that is inserted into the computer's motherboard. It has at least two connectors for connecting to a network cable.
For Ethernet, the ISA standard uses three types of network adapters: 8-bit, 16-bit and 32-bit. The 8-bit adapter can be inserted into 8-bit or 16-bit slots on the motherboard and is used primarily in IBM XT or IBM PC computers that do not have 16-bit slots. Sometimes 8-bit adapters are also purchased for IBM AT computers if the data transfer speed requirements are low. For a 16-bit adapter, you must use a 16-bit slot.
If your computers are based on an 80386 or 80486 processor, it makes sense to consider purchasing a high-speed 32-bit network adapter, at least for those stations that bear the maximum load.
Network adapters can be designed for ISA, EISA or Micro Channel architecture. The first architecture is used in computers of the IBM AT series and compatibles with them, the second - in powerful stations based on 80486 processors, the third - in PS/2 computers from IBM. Please note that these types of adapters are structurally different from each other. While you will be able to fit an ISA adapter into an EISA bus, you will never be able to fit an EISA adapter into an ISA bus. The Micro Channel design is completely ISA and EISA incompatible.
To speed up operation, there may be a buffer on the network adapter board. The size of this buffer varies between adapters different types and can range from 8 KB for 8-bit adapters to 16 KB or more for 16- and 32-bit adapters.
Ethernet network adapters use I/O ports and one interrupt channel. Some adapters can work with a direct memory access (DMA) channel.
The adapter board can contain a read-only memory (ROM) chip to create so-called diskless workstations. These are computers that do not have a hard drive or floppy disks. Loading operating system is executed from the network, and is executed by a program recorded in the remote boot chip.
Before inserting the adapter into the computer motherboard, you must use the switches (located on the adapter board) to set the correct values for the input/output ports, interrupt channel, and base address of the remote boot ROM of the diskless station. We will tell you more about installing switches in the chapter “Network Installation”.
2.1.5. Repeater
If the length of the network exceeds the maximum length of a network segment, it is necessary to split the network into several (up to five) segments, connecting them through a repeater.
Structurally, the repeater can be made either as a separate structure with its own power supply, or as a board inserted into the expansion slot of the computer motherboard.
The repeater as a separate design is more expensive, but it can be used to connect Ethernet segments made on either thin or thick cable, since it has both coaxial connectors and connectors for connecting a transceiver cable. Using this repeater, you can even connect segments made on both thin and thick cables into a single network.
The board repeater has only coaxial connectors and therefore can only connect segments on a thin coaxial cable. However, it is cheaper and does not require a separate outlet for connecting power.
One of the disadvantages of a repeater built into a workstation is that in order to ensure 24/7 network operation, the station with the repeater must also operate 24/7. If you turn off the power, communication between network segments will be disrupted.
The functions of the repeater are to physically separate network segments and ensure the recovery of packets transmitted from one network segment to another.
The repeater increases the reliability of the network, since the failure of one segment (for example, a cable break) does not affect the operation of other segments. However, of course, data cannot pass through the damaged segment.
2.2. Arcnet hardware
To organize an Arcnet network, you will need a special network adapter. This adapter has one external connector for connecting a coaxial cable.
Each Arcnet adapter must have its own number for a given network. This number is set by switches located on the adapter and ranges from 0 to 255.
Network adapters of workstations are connected via a coaxial cable with a characteristic impedance of 93 Ohms to a special device - a hub. It is also possible to use unshielded twisted pair cable.
Hubs are either passive (Passive Hub) or active (Active Hub). One hub (depending on its type) can connect 4, 8, 16 or 32 workstations.
Restrictions for the Arcnet network are given in table. 5.
Table 5. Arcnet Network Limits
The advantages of the Arcnet network are the low cost of network equipment (compared to Ethernet) and the long network length (up to 6 kilometers). However, the low data transfer rate of 2.44 megabits per second limits the use of the Arcnet network.
2.3. Token-Ring equipment
Concerning Token-Ring networks, then its name may mislead you. The topology of this network is more similar to a star topology than a ring topology. Instead of connecting to each other to form a ring, Token-Ring workstations connect radially to an IBM 8228-type hub. True, there can be several hubs, and in this case the hubs are actually combined into a ring through special connectors.
However, if only one hub is used, then the connecting connectors do not need to be looped.
The data transfer speed in the Token-Ring network can reach 4 or
16 Mbits per second, but the cost of network equipment is higher than for an Ethernet network. In addition, there are other restrictions (see Table 6).
Table 6. Restrictions for the Token Ring network
As you can see from this table, Token-Ring networks are not designed for long distances. All computers should be located on one or two floors of the building. The higher hardware cost compared to Ethernet further reduces the appeal of this IBM product.
Loading...
