Question

(6 pts) 6. In carrier-sensing Ethernet, a) why are collisions possible, b) how are they detected and mitigated, c) how are they resolved, and d) address fairness among competing senders

Answer 1

ANSWERS :

ANS 6. a) In carrier sensing ethernet collision are possible because there will surely be a time when 2 users of the medium will send data at the same time. When this situation happens collision occurs.

ANS 6. b) The collision are detected using collision signal , if the collision signal is received during transmission this detects that collision has happened and quickly stops the transmission.

The collision are mitigated as when it is detected that a collision has occurred the main station instantly stops the transmission of data and it also sends signal named jam signal and then wait for some time to resume the transmission.

ANS 6. c) Collisions are resolved in this ethernet as when a collision is detected collision signal received , there is no such special function that happens it's just they detect collision and once detected the transmission is stoped and no data is being transferred and it continues for a random time interval after which again signal are transmitted. Usually we can keep a check on the transmission line thoroughout as to ensure that no 2 devices send the data at the same time this avoiding collision.

ANS 6. d) In this ethernet the address fairness among competition sender means that the senders which are waiting to send data needs to be properly managed i.e no sender should randomly send the data rather there needs to be a fair method that we can adapt which is all the senders should send data in a preodic method as according to the address they are assigned with, so that there is no collision and no sender has to wait for large amount of time.