RE: [ns] RE: Bandwidth in 802.11 simulation

["Antonio Grilo" <amg@cris.inesc.pt>]

Hi Robin

>My understanding is that the bandwidth in 802.11
>depends on many parameters, which are not all in the
>802.11 code (some are in phy.cc...).
I've not been using NS to simulate 802.11 as I have my own simulator.
Nevertheless, I believe that the "bandwidth" parameter corresponds to the
physical crude bit-rate, not being affected by other parameters. Of course
at the MAC layer other parameters affect the "perceived" bandwidth for the
crude bit-rate is also used to transmit overhead information
(preambles+headers+trailers), besides the overhead introduced by the CSMA/CA
algorithm.
So, while I've not checked the code yet, I would expect you to find the
"bandwidth" parameter used in the calculation of frame transmission times
(at least it was like this that I have implemented my own simulator), and
only for the physical payload (the physical preamble and header are always
transmitted at 1 Mbps).

Best regards,
Antonio Grilo