Basic Computer Networks MCQ Question and Answer

Basic Computer Networks MCQ Question and Answer
171. To interface a computer terminal with a modem, the required physical layer standard is
  • RS 424 - A
  • RS 232 - C
  • RS 449
  • Either (b) or (c)
Show Answer
172. Find the maximum data rate of a noiseless 4kHz channel using T1 PCM system
  • 32 Kbps
  • 56 Kbps
  • 80 Kbps
  • 24 Kbps
Show Answer
173. What is the percentage of over head on a T1 carrier (1.544 Mbps) ?
  • 25%
  • 13%
  • 20%
  • 47%
Show Answer
174. Phase shift keying (PSK). method is used to modulate digital signals at 9600 bps using 16 levels. Find the line signals speed (i.e. modulation rate)
  • 2400 bands
  • 1200 bands
  • 4800 bands
  • 9600 bands
Show Answer
175. A 4 kHz noise less channel with one sample every 125 per sec is used to transmit digital signals. Differential PCM with 4 bit relative signal value is used. Then how many bits per second are actually sent ?
  • 32 Kbps
  • 64 Kbps
  • 8 Kbps
  • 128 Kbps
Show Answer
176. A 4 KHz noiseless channel with one sample every 125 per sec., is used to transmit digital signals. Find the bit rate (bits per second) that are sent, if CCITT 2.048 Mbps econdig is used.
  • 500 Kbps
  • 32 Kbps
  • 8 Kbps
  • 64 Kbps
Show Answer
177. A noiseless 3 kHz channel transmits bits with binary level signals. What is the maximum data rate ?
  • 3 Kbps
  • 6 Kbps
  • 12 Kbps
  • 24 Kbps
Show Answer
178. Television channels are 6 MHz. How many bits can be sent if four level digital signals are used (assume a noiseless channel)
  • 24 Mbps
  • 12 Mbps
  • 6 Mbps
  • 36 Mbps
Show Answer
179. A 3000 Hz bandwidth noisy channel transmits bits with a signal to thermal noise ratio of 30 dB. What is the maximum data rate of the channel ?
  • 30 Kbps
  • 90 Kbps
  • 60 Kbps
  • none of these
Show Answer
180. Protocols are
  • agreements on how communiccation components and DET's are to communicate
  • logical communication channels used for transferring data
  • physical communication channels used for transferring data
  • none of the above
Show Answer
Questions and Answers for Competitive Exams Various Entrance Test