2. What is Computer Network? A computer network, often simply referred to as a network, is a collection of computers and devices interconnected by communications channels that facilitate communications among users and allows users to share resources. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

3. For what purposes are networks used? Computer networks can be used for a variety of purposes: Facilitating communications: Using a network, people can communicate efficiently and easily via email, instant messaging, chat rooms, telephone, video telephone calls, and video conferencing. Sharing hardware: In a networked environment, each computer on a network may access and use hardware resources on the network, such as printing a document on a shared network printer. Sharing files, data, and information: In a network environment, authorized user may access data and information stored on other computers on the network. The capability of providing access to data and information on shared storage devices is an important feature of many networks. Sharing software: Users connected to a network may run application programs on remote computers. Information preservation. Security. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

4. What are the types of networks ? LAN WAN WLAN HAN PAN GAN Campus network.... CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

5. LAN(Local Area Network): A network that connects computers and devices in a limited geographical area such as home, school, computer laboratory, office building, or closely positioned group of buildings. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

6. WAN (Wide Area Network): Computer network that covers a large geographic area such as a city, country, or spans even intercontinental distances, using a communications channel that combines many types of media such as telephone lines, cables, and air waves. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

7. WLAN (Wireless Local Area Network ): Also referred to as LAWN. A type of local-area network that uses high-frequency radio waves rather than wires to communicate between nodes. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

8. HAN (Home Area Network): A home network or home area network (HAN) is a residential local area network (LAN).

9. PAN (Personal Area Network): A computer network used for communication among computer and different information technological devices close to one person. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

10. GAN (Global Area Network): a network used for supporting mobile communications across an arbitrary number of wireless LANs, satellite coverage areas, etc. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

11. Campus Network: A computer network made up of an interconnection of local area networks (LAN's) within a limited geographical area. The networking equipments (switches, routers) and transmission media (optical fiber, copper plant, Cat5 cabling etc.) are almost entirely owned (by the campus tenant / owner: an enterprise,university,government etc. ). CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

12. STARTER With the help of the diagram, describe the function of the components of a typical network system: 1. A file server 2. A bridge 3. A router 4. A backbone 5. A LAN 6. A gateway 7. A modem CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

13. A file server: a main computer that provides a storage area for data files on a network CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

14. A bridge: a hardware and software combination used to connect the same type of networks. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

15. A router: a special computer that directs communicating messages when several networks are connected together. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

16. A backbone: the main transmission path, handling the major data traffic, connecting different LANs together. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

17. A gateway: an interface that enables dissimilar networks to communicate such as two LANS based on different topologies or network operating systems. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

18. A modem: a device for converting digital signals to analogues signals and vice versa to enable a computer to transmit and receive data using an ordinary telephone line. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

19. transmit (v): Word Formation : transmission (n), transmitter (n) Definition : to send or convey from one person or place to another Synonyms : pass Collocations : transmit to, transmit data/ information Ex: The data will be automatically transmitted from one part of the system to another. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

20. partition (v): Word Formation : partition (n), partitioner (n) Definition : to divide sth into two parts Ex : The hall was partitioned to contain the noise of the computers CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

21. interface(n): Definition : The point of interaction or communication between a computer and any other entity, such as a printer or human operator. Ex: My computer has a network interface, which allows me to get to other computers. Ex: The new version of the program comes with a much better user interface(= way of showing information to a user) than the original. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

22. vice versa (adv.) : Definition : with the order reversed; the other way around (the opposite of what has been said) Ex: Can we use a computer monitor as TV and vice versa ? CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

23. component (n): Definition : A part of a mechanical or electrical complex. Synonyms : part Ex: A hard drive, a mouse and a keyboard are some of the components of a computer. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

24. WiFi hotspot (n.phr.): Definition: A WiFi hotspot is a site that offers Internet access over a wireless local area network through the use of a router connected to a link to an Internet service provider.WiFi Hotspots are usually found in coffee shops and restaurants. Ex: When I have free time to spend alone, I find a cafe with wifi hotspot and I connect to the Internet. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

25. i nterference (n): Word Formation : interfere (v) Definition : changing, modifying, or disrupting a message as it travels along a channel between a source and a receiver. Typically the term refers to the addition of an unwanted signal to the useful signal. Ex: Some time ago, the interference problem was more common while using WIFI. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

26. intercept (v.) : Word Formation : interception (n) Definition : to receive a communication or signal directed elsewhere usually secretly Collocations : intercept data Ex: Nowadays there are a lot of hackers who intercept the data of other people from their computers. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

27. encrypt (v) : Word Formation : encryption (n) Definition : to convert data or information into code especially to prevent unauthorized access Antonym : decrypt Collocations :encryption programme Ex: We should encrypt the message for security reasons. Ex:Messages encrypted using the public key can be decrypted only by someone with the private key. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

28. READING Read the text and the diagram of wireless network setup.Match the diagram key to the components of the network. 1. B 2. C 3. A 4. D 5. E 6. F CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

29. layer (n): Definition : one of the several levels of network communication system. Collocations : network layer Ex: communication process among computers has a lot of layers such as application layer, presentation layer and session layer. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

30. interpret (v.) : Word Formation : interpretation (n) Definition : to give or provide an explanation of sth. Collocations : interpret the data Ex: This programme interprets the data in a langauge that is easily understood. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

31. compress (v.) : Word Formation : compression (n.) Definition : To transform (data) to minimize the space required for storage or transmission Collocations : compress a file Ex:. She compressed the file in order to download it efficiently CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

32. node (n.): Definition : A terminal in a computer network Ex: Each node has a different function in the network. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

33. half-duplex (adj. phr.) : providing communication in both directions, but only one direction at a time (not simultaneously). full-duplex (adj.phr.): allowing communication in both directions, and, unlike half-duplex, simultaneously. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

34. checksum tests (n. phr.) : a digit representing the sum of the digits in an instance of digital data; used to check whether errors have occurred in transmission or storage. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

35. scramble (v.) : Word Formation : scrambled (adj) Definition to change a radio or telephone signal so that it can only be understood using a special device Ex: They will scramble the data so that nobody can read it. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

36. supervise (v.) : Word Formation : supervision (n) supervisor (n) Definition : to direct or watch the operation of something or somebody. Collocations : carefully supervise, supervise operation Ex: The children play while two teachers supervise them. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

37. medium (n.) : Definition : A means /agency for storing or communicating information. Collocations : medium of communication Ex: Devices with wireless technology uses radio waves as the medium of transmission. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

38. verify (v.) : Word Formation : verification (n) Definition : to determine and test the truth of something. Synonyms : justify Ex: Are you able to verify your account? Ex: These figures are surprisingly high and they'll have to be verified. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

39. network congestion (n.): Definition : network congestion occurs when a link or node is carrying so much data that its quality of the service gets worse. CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

40. Specialist Reading- KEY 1. a. Segments b. Packets 2. To determine if the data was scrambled during transmission 3. Until it receives confirmation from the next point along the route that the packet has arrived undamaged 4. a. The checksum is calculated and verified for each packet b. The message may be rerouted to avoid congestion on the network CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

41. 5. a. Presentation Layer b. Transport Layer c. Physical Layer d. Data-link layer e. Application layer f. Session layer g. Network layer h. Transport layer i. Data-link layer CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

42. PART B- Key 1 2 a. iii b. i c. iv d. ii a. T b. F c. T d. T e. F f. T g. T CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT

43. Page 77 Exercise 3: a. Presentation Layer b. Transport Layer c. Network Layer d. Session Layer e. Application Layer C--- bits G---data link, logs F---packets, security A---trasport, segments H---held, session, complete D--- layer B--- expanded, decrypted E---readable CANKAYA UNIVERSITY - OFFICE OF BASIC AND ELECTIVE COURSES- ENGLISH UNIT