- •Part 7. Mixed Networks
- •Part 8. Routers and Switches
- •Part 9. Packet-switching
- •Essential vocabulary (7), (8), (9)
- •Exercises
- •1. Find in parts 7, 8 and 9 of the text English equivalents for the following words and phrases:
- •8. Translate the passages in writing:
- •9. Answer the following questions using the information from parts 7, 8 and 9 of the text.
- •10. Look through parts 7, 8 and 9 of the text and mark the statements as true (t) or false (f). If you think a statement is false, change it to make it true.
- •11. Make summary of parts 7, 8 and 9 of the text.
- •12. Read the following text and fill in suitable words from the box.
- •The osi Reference Model
- •A) Make your own sentences with the words in bold type. B) Make short summary of the text.
- •13. Look at the table below. Match the osi layers with the functions they are responsible for.
- •14. Render the following text in English. Модель osi
Essential vocabulary (7), (8), (9)
Words
algorithm n |
discard v |
operability n |
announcement n |
incur v |
OSI |
AppleTalk n |
initial adj |
pass through v |
cost-effective adj |
IPX |
payload n |
CRC |
layer n |
radically adv |
datalink n |
look up v |
|
Word Combinations
mixed network |
lookup table |
cost-effective network |
the payload of the frame |
OSI Reference Model |
cut-through switch |
to announce one`s presence |
store-and-forward switch |
browser list |
fragment-free switch |
specific destination |
to check for CRC errors |
to keep smth. separate from smth. |
error correction |
packet-switching |
error level |
current packet |
|
Exercises
1. Find in parts 7, 8 and 9 of the text English equivalents for the following words and phrases:
смешанная сеть; заменить все концентраторы коммутаторами; создавать эффективную и, при этом, рентабельную сеть; эталонная модель взаимодействия открытых систем; полностью изменить способ …; работать на втором уровне модели OSI; отличаться от алгоритмов, используемых маршрутизаторами; быть существенным для работоспособности сети; всякий раз, когда; осуществлять широковещательную рассылку; сообщить о чьём-л. присутствии; добавлять компьютер в список просмотра; сообщать остальной части сети; независимо от того, куда …; государственная граница; пограничник; пропускать пакет данных; основываться на пакетной коммутации; отправлять текущий пакет данных; сохранять в область временной памяти; сравнивать со списком адресов; сохранять в таблицу поиска коммутатора; содержать в себе полезную нагрузку кадра; источник и получатель пакета; три способа маршрутизации трафика; сквозная коммутация; коммутация с промежуточным хранением (буферизацией) пакетов; обнаруживать пакет; после сохранения 6 байтов …; проверять на наличие CRC ошибок; сохранять в буфер целый пакет; иначе; достигать определённого уровня ошибок; не обеспечивать исправление ошибок; большинство ошибок и все конфликты происходят во время …
2. Transcribe and learn to read the following words:
incurred, wonder, concept, announcement, rely, immediately, initial, algorithm.
3. Write the Past Indefinite and the Past Participle of the verbs:
cast, wonder, announce, add, let, pass, rely, send, read, begin, check, discard.
4. Find in parts 7, 8 and 9 of the text antonyms to the following words and word combinations:
unprofitable, to maintain, dispensable, absence, indirectly, to interrupt a connection, permanent memory, a portion of the packet, to discard, final.
5. Give all possible derivatives of the following words. Use dictionary if necessary.
To combine, to announce, specific, to separate, to operate, to depend, memory.
6. Write the expansions of the following abbreviations and learn them:
OSI Reference Model, IP, IPX.
7. Match the words on the left with their definitions on the right.
1. OSI reference model |
a. a message-delivery technique in which small units of information (packets) are relayed through stations in a computer network along the best route available between the source and the destination. |
2. Layer |
b. a collection of stored results that can be accessed very rapidly by a program without the need to calculate each result whenever needed. |
3. Packet switching |
c. a method of delivering transmissions in which messages are held temporarily by an intermediary before being sent on to their destination. |
4. Header |
d. a layered architecture (plan) that standardizes levels of service and types of interaction for computers exchanging information through a communications network. |
5. Look-up table |
e. a network switch that routes packets immediately to the port associated with the packet’s recipient. |
6. Cut-through switch |
f. a temporary storage area for data waiting to be processed. |
7. Store-and-forward |
g. the protocol or protocols operating at a particular level within a protocol suite, such as IP within the TCP/IP suite. |
8. Buffer |
h. the portion of a data packet that precedes the body (data). It contains data, such as source and destination addresses and control and timing information that is needed for successful transmission. |