DOEACC Society 2006 DOEACC C Level C7 Advanced Computer Networks ( ) - Question Paper

C7-R3: ADVANCED COMPUTER NETWORKS
NOTE:
Time: three Hours Total Marks: 100
1.
a) elaborate the drawbacks of shortest path routing?
b) “In one-persistent CSMA, collisions can occur indefinitely.” Comment.
c) Distinguish ranging from Available Bit Rate (ABR) and Unspecified Bit Rate (UBR) services
in ATM.
d) elaborate functional grouping and reference points (interfaces) in ISDN?
e) How does FDDI-II give both asynchronous and synchronous data transfer services?
f) elaborate various PDUs in SNMPv2 protocol?
g) What is the significance and use of flow tag in IPv6 header?
(7x4)
2.
a) Establish the Markov Chain for M/M/S queuing system. Hence find the probability of
the M/M/¥ system being in state n.
b) State Jackson’s theorem for network of queues.
c) State Burke’s theorem for M/M/S queue.
(10+4+4)
3.
a) Using throughput vs backlog conditions, discuss the unstable nature of slotted ALOHA.
b) In a tree algorithm for collision resolution in slotted ALOHA, the feedback sequence is
e,e,1,e,0,e,1,1,0. Here e implies collision, one implies successful transmission and 0
implies idle condition. find the binary rooted tree for the above.
(9+9)
4.
a) Show the ATM protocol reference model and discuss functions of different layers and
planes in the above.
b) In an ATM user-network interface (UNI), the minimum allowable cell inter-arrival time is
T sec and the tolerable cell delay variation is L sec. A sender inputs successive cells at
time instants k(T - Î ) where Î = 03L and k =0,1,2,3,4,5,6. check the conformance of
cells using Leaky Bucket algorithm.
(9+9)
5.
a) In situation of FDDI, how are different counters/timers operated? Under what condition(s)
asynchronous allocation is not done?
b) Show the DQDB network topology and discuss why this protocol is unfair.
(10+8)
C7-R3 Page one of two July, 2006
1. ans ques. one and any 4 ques. from two to 7.
2. Parts of the identical ques. should be answered together and in the identical
sequence.
6.
a) In OSPF, elaborate the metrics used to calculate link costs?
b) In the Border Gateway Protocol (BGP), elaborate the functional procedures involved in its
operation? How are these procedures implemented?
(8+10)
7.
a) How is congestion window managed in the slow begin algorithm in TCP?
b) elaborate the types of replies generated by SMTP protocol? Illustrate with examples.
(9+9)
C7-R3 Page two of two July, 2006

Earning:   Approval pending.