1
GATE CSE 2009
+2
-0.6
Frames of 1000 bits are sent over a 106 bps duplex link between two hosts. The propagation time is 25 ms. Frames are to be transmitted into this link to maximally pack them in transit (within the link).
What is the minimum number of bits (I) that will be required to represent the sequence numbers distinctly? Assume that no time gap needs to be given between transmission of two frames.
A
I = 2
B
I = 3
C
I = 4
D
I = 5
2
GATE CSE 2007
+2
-0.6
The message 11001001 is to be transmitted using the CRC polynomial x3 + 1 to protect it from errors. The message that should be transmitted is:
A
11001001000
B
11001001011
C
11001010
D
110010010011
3
GATE CSE 2007
+2
-0.6
The distance between two stations M and N is L kilometers. All frames are K bits long. The propagation delay per kilometer is t seconds. Let R bits/second be the channel capacity. Assuming that processing delay is negligible, the minimum number of bits for the sequence number field in a frame for maximum utilization, when the sliding window protocol is used, is:
A
$$\left\lceil {{{\log }_2}{{2LtR + 2K} \over K}} \right\rceil$$
B
$$\left\lceil {{{\log }_2}{{2LtR} \over K}} \right\rceil$$
C
$$\left\lceil {{{\log }_2}{{2LtR + K} \over K}} \right\rceil$$
D
$$\left\lceil {{{\log }_2}{{2LtR + 2K} \over {2K}}} \right\rceil$$
4
GATE CSE 2006
+2
-0.6
Station A uses 32 byte packets to transmit messages to Station B using a sliding window protocol. The round trip delay between A and B is 80 milliseconds and the bottleneck bandwidth on the path between A and B is 128 kbps. What is the optimal window size that A should use?
A
20
B
40
C
160
D
320
GATE CSE Subjects
EXAM MAP
Medical
NEET