Basic Computer Networks MCQ Question and Answer
Basic Computer Networks MCQ Question and Answer
161. Three routers have to be inter-connected in a point-to-point network. Each pair of routers may be connected by a high speed line, a medium speed line, a low speed line or no line. If the time taken to generate and inspect each topology, is 100 ms.How long will it take to inspect all of them to find one that best matches the expected load ?
- 12 sec
- 14.4 sec
- 6.4 sec
- 7.0 sec
162. Data link layer retransmits the damaged frames in most networks. If the probability of a frame's being damaged is p. What is the mean number of transmissions required to send a frame if acknowledgements are never lost ?
- K/(K-P)
- 1/(K-P)
- K/K(1+P)
- P/(K+1)
163. A circuit switching network has the following characteristics.
Set up time = 5 sec
Propagation = 5 sec
Message size = 1 M bits
Data transmission rate = 1 M bits
Data transmission rate = 1 Kbps
Number of hops = 10
When will the last bit of the message reach the receiver ?
- t = 520 sec
- t = 1000 sec
- t = 250 sec
- t = 1025 sec
164. A networking system has an n layers. Application generated message of length M bytes. At each of the layer, a h-byte header is added, what fraction of the network bandwidth is filled with headers ?
- M/(n*M) bytes
- h*n*M bytes
- (n*h)/M bytes
- M/(n*M)
165. A designer wants to design a point-to-point subnetwork with10 routers of full duplex line. then the total number of lines among them would be
- 10
- 20
- 45
- 90
166. A network designer wants to connect 5routers as point-to-point simplex line. Then the total number of lines required would be
- 5
- 10
- 20
- 32
167. Two networks each provide reliable connection-oriented service. One of them offers a reliable byte stream and the other offers a reliable message stream. A process writes 1024 bytes, then
- both networks will receive 2048 bytes as a single unit
- message stream network will receive 1024 bytes only at one time. But byte stream network will receive 2048 bytes as a single unit.
- message stream network receives 2048 bytes as a whole. But bytes stream 1024 bytes only at a time.
- both will receive 1024 bytes at one time since there is a gap between writes.
168. Frames are generated by
- DLL in OSI mode, SATNET in TCP/IP, TC in ATM
- DLL in OSI mode, TC in TCP/IP, SATNET in ATM
- DLL in OSI mode, ARPANET in TCP/IP, PMD in ATM
- DLL in OSI mode, PMD in TCP/IP, ARPANET in ATM
169. A packet switching network (highly loaded) has the following characteristics propagation delay = 2 sec/hp. Data transmission rate = 1. Packet size = r bit = 512 bits. Number of hops = 10.
At what time the last bit of the last packet will reach the receiver ?
- 1024.5 sec
- 1038 sec
- 2048 sec
- 512 sec
170. For a packet switching network where
packet size = p bits
Message size = x bits
Propagation delay = d sec/hop
Number of hops = k hops
Then find the time required for the last bit of the last packet to reach the receiver.
- t = x/p + k (d + p/d) sec
- t = x/p + k (d +b) sec
- t = x/p + k (d + b) sec
- t = x + b + (k - 1) xp/b + kd sec