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Hierarchical network
Text 22
Bus Network
Words and word combinations:
Single length of wire – провод единой длинны
travel along this cable – проходит вдоль этого кабеля
а host computer – головной компьютер
to hook up – соединять
intended recipients – предназначенные приемники
as efficient as – такой же эффективный как
In a bus network, a number of computers are connected by a single length of wire, cable, or optical fiber. All communications travel along this cable, which is called a bus. There is no host computer or the server. The bus network is often used to hook up a small group of microcomputers that share data. The microcomputers are programmed to ‘check’ the communications that travel along the bus to see if they are the intended recipients. The bus network is not as expensive as the star network, and, if one of the microcomputers fails, it does not affect the entire network. However, the bus network is not as efficient as the star network.
Bus network
Ring Network
Words and word combinations:
A ring network – кольцевая сеть
a loop – виток
susceptible – восприимчивый, поддающийся
to breakdown – поломаться
A ring network is much like a bus network, except the length of wire, cable, or optical fiber connects to form a loop. This type of configuration does not require a central computer to control activity. Each computer connected to the network can communicate directly with the other computers in the network by using the common communication channel, and each computer does its own independent applications processing. When one computer needs data from another computer, the data is passed along the ring. The ring network is not as susceptible to breakdown as the star network, because when one computer in the ring fails, it does not necessarily affect the processing or communications capabilities of other computers in the ring.
Ring network
Exercises:
1. Give Russian equivalents of the following phrases:
A number of computers; no host computer; a small group of microcomputers; is much like a bus network; own independent applications; is not as susceptible; communications capabilities
2. Say if the following sentences are true or false.
1. In a bus network, a number of computers aren’t connected by a single length of wire, cable, or optical fiber. 2. The bus network is often used to hook up a small group of microcomputers that share data. 3. The bus network is as expensive as the star network, and, if one of the microcomputers fails, it does not affect the entire network. 4. This type of configuration requires a central computer to control activity. 5. Each computer connected to the network can communicate directly with the other computers in the network by using the common communication channel.
3. Insert missing words, use the text’s vocabulary:
1. In a bus network, a number of computers are … by a single length of wire, cable, or optical fiber. All communications travel along this cable, which is called a … . 3. A ring network is much like a bus network, except the length of wire, cable, or optical fiber connects to form a … . 4. When one computer needs data from … computer, the data is passed along the ring. 5. The ring network is not as … to breakdown as the star network, because when one computer in the ring fails, it does not necessarily affect the processing or communications capabilities of other computers in the ring.
4. Translate these sentences into your native language:
1. There is no host computer or the server. The bus network is often used to hook up a small group of microcomputers that share data. 2. The microcomputers are programmed to ‘check’ the communications that travel along the bus to see if they are the intended recipients. 3. Each computer connected to the network can communicate directly with the other computers in the network by using the common communication channel, and each computer does its own independent applications processing. 4. When one computer needs data from another computer, the data is passed along the ring.
Retell the text.
Text 23
Token Ring Network
Words and word combinations:
Token ring network – сеть подобие кольца
a lull – перерыв, временное затишье
garbled – искаженный
random period – случайный период
to eliminate – устранить, исключить
a predefined pattern of bits – система предопределения битов
In early 1986, IBM announced a new local area network for personal computers using the ring network configuration called the token ring network. Before the token system was established, existing ring networks used the following approach:
· A computer with a message to transmit monitored network activity, waited for a lull, and then transmitted the message.
· This computer then checked to determine if other computers in the network were trying to transmit a message at the same time, which might have garbled its message.
· If two or more computers did try to send messages at the same time, then both waited a different random period of the time and tied to retransmit their message.
Obviously, this procedure led to some message garbling and loss of time and productivity. In the token ring network, designed to eliminate these problems, a predefined pattern of bits, or token, is passed from computer to computer in the network. When a computer receives the token, it is allowed to transmit its message. Then the token is passed on. This method for transmitting messages (which can also use in the bus network) prevents two computers from transmitting at the same time. The IBM token ring network is expensive but efficient. It can link up 250 stations per ring over distances of about 770 yards, and separate rings can be linked to form larger networks.
Exercises:
1. Give Russian equivalents of the following phrases:
A new local area network; using the ring network configuration; following approach; trying to transmit a message; then both waited; receives the token; prevents two computers from transmitting.
2. Say if the following sentences are true or false.
1. In early 1966, IBM announced a new local area network for personal computers using the ring network configuration called the token ring network.
2. A computer with a message to transmit monitored network activity, didn’t wait for a lull, and then transmitted the message. 3. This computer then checked to determine if other computers in the network were trying to transmit a message at the same time, which might have garbled its message. 4. If two or more computers did try to send messages at the same time, then both waited a different random period of the time and tied to retransmit their message. 5. It can’t link up 250 stations per ring over distances of about 770 yards, and separate rings can be linked to form larger networks.
Token ring network
3. Insert missing words, use the text’s vocabulary:
1. A computer with a message to transmit … network activity, waited for a lull, and then transmitted the message. 2. This computer then checked to … if other computers in the network were trying to transmit a message at the same time, which might have garbled its message. 3. If two or more computers did try to send … at the same time, then both waited a different random period of the time and tied to retransmit their message. 4. In the token ring network, designed to … these problems, a predefined pattern of bits, or token, are passed from computer to computer in the network. 5. This method for … messages (which can also used in the bus network) prevents two computers from transmitting at the same time.
4. Translate these sentences into your native language:
1. Obviously, this procedure led to some message garbling and loss of time and productivity. 2. In the token ring network, designed to eliminate these problems, a predefined pattern of bits, or token, is passed from computer to computer in the network. 3. The IBM token ring network is expensive but efficient. It can link up 250 stations per ring over distances of about 770 yards, and separate rings can be linked to form larger networks.
Retell the text.
Text 24