Consider a token ring network with a length of 2 km having 10 stations…
2014
Consider a token ring network with a length of 2 km having 10 stations including a monitoring station. The propagation speed of the signal is 2 × 10଼ m/s and the token transmission time is ignored. If each station is allowed to hold the token for 2 µsec, the minimum time for which the monitoring station should wait (in µ sec)before assuming that the token is lost is _______.
Attempted by 47 students.
Show answer & explanation
Correct answer: 28
Key idea: the monitoring station should wait for one full ring propagation plus the maximum time all other stations could hold the token.
Propagation delay around the ring = ring length / propagation speed = 2000 m / (2 × 10^8 m/s) = 1 × 10^-5 s = 10 µs.
Maximum token holding by other stations = (number of other stations) × (max hold time per station) = 9 × 2 µs = 18 µs.
Total minimum wait = propagation delay + maximum holding = 10 µs + 18 µs = 28 µs.
Answer: 28 µs