Data Communication and Computer Networks - Data Communication
71. In which routing method do all the routers have a common database ?
- Option : B
- Explanation : In link state routing each router creates its own link state packet (LSP). Every other router receives this LSP through the flooding process. All routers therefore have the same information. This is compiled into the link state database.
- Option : D
- Explanation : Full duplex  means transmission and reception can take place simultaneously. So we need 1 line for transmission and 1 for reception. that means between any 2 devices there will be 2 lines.
So Number  of connections 10C2 = 45
Number  of lines required will be =  45*2=90
75. Maximum data rate of a noiseless 4 kHz channel using T1 PCM system is
- Option : B
- Explanation : In this case 8000 samples/sec are possible. With T1, 7 bits are sent per per sample. The data rate is 56 kbps.
