计网大题例题

• 640,000bits from host A to host B over a circuit-switched network
  all link speeds:1.536Mbps
  each link used TDM with 24 slots/sec
  500 msec to estaablish end-to-end circuit

solution:
Bandwidth of a slot link:1.536Mbps/24=64kbps,
Time:(640kb)/(64kbps)+0.5s=10.5s
N links ->1 time
时分复用中要搞清楚什么是帧什么是时隙 此题中显然一帧里有24个时隙