[ns] A bug in ns 802.11 implementation?

[s0g9033 <s0g9033@unix.tamu.edu>]

Hello ns-users,

This could be a bug in mac-802.11.cc.

In function Mac802_11::recvACK(..), which is executed upon the receipt
of an ACK, the Mac does a backoff before sending again, by calling
Backoff_.start(cw_, is_idle()). Shouldn't it wait for a DIFS interval
before calling Backoff_.start(..)? This can be fixed by calling 
mhDefer_.start(difs_) before Backoff_.start(..) in the same function.

Please refer to section 9.2.5.2 of IEEE 802.11 specifications (June 1997)
on Backoff procedure, which states that "All backoff slots occur
following a DIFS period during that the medium is determined to be idle
for the duration of the DIFS period,..".

Regards,
Seema