Computer Network GATE CS and IT previous year questions with Answer
Ques 31 Gate 2016 Set-1
A sender uses the Stop-and-Wait ARQ protocol for reliable transmission of frames. Frames are of size 1000 bytes and the transmission rate at the sender is 80 Kbps (1Kbps = 1000 bits/second). Size of an acknowledgement is 100 bytes and the transmission rate at the receiver is 8 Kbps. The one-way propagation delay is 100 milliseconds. Assuming no frame is lost, the sender throughput is __________ bytes/second.
a is the correct answer.
Ques 32 Gate 2016 Set-1
An IP datagram of size 1000 bytes arrives at a router. The router has to forward this packet on a link whose MTU (maximum transmission unit) is 100 bytes. Assume that the size of the IP header is 20 bytes. The number of fragments that the IP datagram will be divided into for transmission is________
a is the correct answer.
Ques 33 Gate 2016 Set-1
For a host machine that uses the token bucket algorithm for congestion control, the token bucket has a capacity of 1 megabyte and the maximum output rate is 20 megabytes per second. Tokens arrive at a rate to sustain output at a rate of 10 megabytes per second. The token bucket is currently full and the machine needs to send 12 megabytes of data. The minimum time required to transmit the data is _________________ seconds.
a is the correct answer.
Ques 34 Gate 2016 Set-1
Consider that B wants to send a message m that is digitally signed to A. Let the pair of private
and public keys for A and B be denoted by K-x
and K+x
for x = A,B, respectively. Let Kx(m)
represent the operation of encrypting m with a key Kx and H(m) represent the message digest.
Which one of the following indicates the CORRECT way of sending the message m along
with the digital signature to A?
Ques 35 Gate 2016 Set-1
Which of the following is/are example(s) of stateful application layer protocols?
(i) HTTP
(ii) FTP
(iii) TCP
(iv) POP3
Ques 36 Gate 2016 Set-1
Which one of the following protocols is NOT used to resolve one form of address to another one?
Ques 37 Gate 2016 Set-1
Which one of the following protocols is NOT used to resolve one form of address to another one?
Ques 38 Gate 2015 Set-3
Consider a network connecting two systems located 8000 kilometers apart. The bandwidth of the network is 500 × 106 bits per second. The propagation speed of the media is 4 × 106 meters per second. It is needed to design a Go-Back-N sliding window protocol for this network. The average packet size is 107 bits. The network is to be used to its full capacity. Assume that processing delays at nodes are negligible. Then, the minimum size in bits of he sequence number field has to be ________.
a is the correct answer.
Ques 39 Gate 2015 Set-3
Consider the following statements.
I. TCP connections are full duplex.
II. TCP has no option for selective acknowledgment
III. TCP connections are message streams.
Ques 40 Gate 2015 Set-3
Consider a CSMA/CD network that transmits data at a rate of 100 Mbps (108 bits per second) over a 1 km (kilometre) cable with no repeaters. If the minimum frame size required for this network is 1250 bytes, what is the signal speed (km/sec) in the cable?