30-10-2012, 12:53 PM
IV B.Tech I Semester Regular Examinations - COMPUTER NETWORKS
COMPUTER NETWORKS.pdf (Size: 88.99 KB / Downloads: 30)
1. (a) Compare and contrast OSI and TCP/IP models.
(b) Draw and explain in detail about ISO-OSI reference model. [8+8]
2. (a) The following data fragment occurs in the middle of a data stream for which
the character-stuffing algorithm described in the text is used: DLE, STX, A,
DLE, B, DLE, ETX. What is the output after stuffing?
(b) When bit stuffing is used, is it possible for the loss, insertion, or modification
of a single bit to cause an error not detected by the checksum? If not, why
not? If so, how? Does the checksum length play a role here?
© Data link protocols almost always put the CRC in a trailer, rather than in a
header. Why? [6+6+4]
3. (a) Explain five key Assumptions in Dynamic channel allocation in LANs and
MANs.
(b) Explain the multiple access protocol using which the stations about their trans-
missions as soon as they detect a collision? [8+8]
4. (a) What are the problem which caused demise of distance vector routing? Ex-
plain the algorithm that replaced it?
(b) With an example, explain Distance Vector Routing algorithm? [8+8]
5. (a) Explain Berkeley socket primitives for TCP.
(b) Briefly explain the concept of Addressing in TL. [8+8]
6. (a) Briefly discuss about Internet work Routing.
(b) Briefly discuss about Fragmentation. [8+8]
7. (a) Can AAL 1 handle messages shorter than 40 bytes using the scheme with the
Pointer field? Explain your answer.
(b) Suppose that you are measuring the time to receive a TPDU. When an inter-
rupt occurs, you read out the system clock in milliseconds. When the TPDU
is fully processed, you read out the clock again. You measure 0 msec 270,000
times and 1 msec 7,30,000 times. How long does it take to receive a TPDU?
© What is the payload size of the maximum length message that fits in a single
AAL 3/4 cell?