1. What are the two reasons for using layered protocols?
2. What do you mean by link to link layers of OSI reference model? Explain their functions briefly?
3. Write a short note on ISDN?
4. What is the difference between boundary level masking and non- boundary level masking? Give examples
5. Draw the IP datagram header format. “IP datagram has a checksum field still it is called an unreliable protocol”. Justify?
6. What are the principles that were applied to arrive at the seven layers in OSI model?
7. Explain the working of 3 bit sliding window protocol with suitable example.
8. Explain the following ARQ techniques in detail
1. Stop and wait ARQ
2. Selective repeat ARQ
9. What are the reasons for using layered protocols ?
10. 10 Enumerate the main responsibilities of data link layer ?
11. Is the nyquist theorem true for optical fibre or only for copper wire ? Explain.
12. Why do data link layer protocols position the checksum in the trailer and not in the header ?
13. Compare the maximum window size in go-back-N and selective-repeat ARQs.
14. Why does ATM use the cell of small and fixed length ?
15. Give the equivalent binary word for the polynomial x8+x2+x+1.
16. In which of the 7 layers of OSI will a service handling conversion of characters is from EBCDIC to ASCII be normally implemented ?
17. Where is the special IP address 127.0.0.0. used ?
18. Convert the IP address 220.127.116.11 into binary ?
19. Compare satellite with fiber as a communication medium and enumerate the application areas where satellite still holds a niche(or special)marker.
20. A binary signal is sent over a 3-khz channel whose signal-to-noise ratio is 20 db.Calculate the maximum achievable data rate ?
21. What does ‘data transparency’ mean ? With the help of a flow chart, explain the process of bit de-stuffing at the receiver’s end.
22. Assuming classful addressing, find the no of subnets and the no of hosts per subnet foe the following blocks:
(ii) A class B block having mask of 255.255.192.0
23. Write short note on any four of the following:
(a) The ATM reference model
(c) Salient difference between ISO-OSI and TCP/IP models.
(d) Network Topologies and their uses.
(e) Wireless networks.
24. (a) Differentiate between static and dynamic channel allocation.
(b) List out the main responsibilities of the network layer.
(c) Give two examples of a ‘collision-free’ protocol ?
(d) Why is IP called ‘best-effort delivery’ protocol?
(e) What is a transparent bridge?
(f) what are the two sub layers of data link layer called ?
(g) What are the other names of IEEE 802.11 protocol or standard?
(h) What is the baud rate of a standard 10 mbps Ethernet LAN ?
(i) What is a minimum data size of an Ethernet frame ?
25. Explain distance vector routing . What are its limitations and how are they overcome?
26.Explain pure-ALOHA and slotted- ALOHA systems.Give the expression for throughout for each,clearly explaining the various terms.
27. Explain 1-persistent, p-persistent and 0-persistent CSMA giving strong and weak points of each.
28. Explain network equipment used in wired-LANS and explain the function of Hub, Switch, and bridge.
29. Write short note on any four of the following:
(a) Token ring
(b) Various fields in Ethernet frame format
(c) Difference between congestion control and QoS(or Quality of service)
(e) Traffic shaping using token bucket algorithm
30. If the transmitted code word is 10011000 and the received code word is 11001001. What is the error word ? Write transmitted code word , received code word and error word as polynomials.
31.Why transport layer protocols like TCP and UDP are called end-to-end protocols. What is the difference between them?
32. Differentiate between:
(i) Baseband co-axial cable and broad band coaxial cable
(ii) Optical fibre and twisted pair
(iii) SMTP and SNMP
33. What are the basic functions of the data link layer? Write down the basic features of HDLC protocol? Could HDLC be used as a data link protocol for a LAN? Justify your answer.
34. The physical layer service is a non-confirmed service. Assume that some bits of data are lost during transmission over physical media,which layer will detect the loss and take some remedial measures. Explain any one method clearly depicting how this operation is performed.
35. What are the advantages of cell switching that is used in ATM?
36. Outline and discuss the main fields in Ethernet IEEE 802.3 frame. What are the main objectives of preamble ?
37. What is the average number of transmission required to send a frame of length 1600 bytes correctly, if the bit error rate is 1 x 10-6.
38. Explain what is meant by the term ‘integrated service digital network’. Give three reasons a company might choose an ISDN link in preference to a leased line.
39. Subnet the class C network address 18.104.22.168 into eight subnets. Why are the ‘all ones’ and ‘all zeroes’ subnets not used ?
40.What do you understand by the term ‘structured cabling’. State the main rules that should be used when installing a cable. Show that maximum cabling area for LAN for horizontal cabling runs is approximately 200m.
41. What are the various classes of IP addressing? Calculate the maximum number of class A, B and C network Ids.
42. Why is a data link layer switch preferred over a hub ?
43. Which device is needed to connect two LANs with different network Ids ?
44. When is a translating bridge used ?
45. Can a switch be used to connect two LANs with different network IDs ?
46. Write two ways in which computer applications differ from network applications ?
47. What is count to infinity problem ?
48. What was the reason for selecting a speed of 155.52 Mbps in the original ATM standard ?
49. Contrast link state and distance vector routing protocols, giving an example of each.
50. What is ISO-OSI reference model ? Compare it with TCP/IP reference model. Why TCP/IP reference model is more popular than OSI model ? Which layer is used for the following :
(i) to route packets
(ii) to convert packets to frame
(iii) to detect and correct errors
(iv) to run services like FTP, Telnet etc.
51. Discuss Shannon’s capacity. What implications does it have ?
52. Discuss how satellite network differs from traditional networks such as Ethernet, Tokenbus.
53. What is packet switching ? Explain two different approaches of packet switching. ?
54. Doscuss the different factors affecting congestion control algorithms. ?
55. How does a token ring network work ? In what way is it different from Ethernet ?
56. Describe and distinguish between FDMA, TDMA, and CDMA.
57. Discuss the following terms with respect to ATM: VPI, UNI, asynchronous, AAL, Cell , PVC.
58. What is sliding window protocol ? Differentiate between stop-and wait ARQ and Go-back-N protocol.
59. Differentiate between ISO-OSI and TCP/IP reference model.
60. Explain leaky bucket algorithm and compare it with token bucket algorithm.
61. Explain ATM reference model.
62. Explain different kinds of Switching techniques.
63. Differentiate between Link state and Distance Vector Routing algorithm.
64. Explain network layer in ATM,
65. Differentiate between IEEE 802.3, IEEE 802.4 and IEEE 802.5 standards.
66. Explain any three error detection and correction techniques.
67. Explain various cabling techniques used in IEEE 802.3 standard,