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RE: [ethmac] Collisions



See 802.3 4.2.3.2.5:
 "At the end of enforcing a collision (jamming), the CSMA/CD sublayer delays
 before attempting to retransmit the frame. The delay is an integer multiple
 of slot time. The number of slot times to delay before the nth
 retransmission attempt is chosen as a uniformly distributed random
 integer r in the range:  0 <= r < 2^k where k = min (n,10)."

After 16 attempts at transmission, all resulting in collisions, the packet
should be dropped.  (Slot time is 512 bit times, BTW).

 - WJ

-----Original Message-----
in any case in respect to collision and backoff algoritum the spec specify
(I hope I recall it correct, and if not do corret me) that you will
randomize a number between 0-2^k where K is the number of consecutive
collision and K go up to 10 so after the fisrt collision the random number
can be 0 or 1 after the second consecutive colision the random number can
be 0,1,2,3 and so on. and after the 16 consecutive collision the station
can discard the packet.