Hi,

I'm considering using the USRP together with the 802.11 stack to prototype
some 802.11 MAC layer changes. I'm sending from an 11b card at the base rate
to my USRP/RFX2400.

One shortcoming at present is that the code doesn't generate ACKs for
received frames. There are quite strict timing requirements for ACK
generation: for 11b at the base rate the ACK should be sent within a period
measured in microseconds. I can increase the ACKTimeout but apparently
there's a hard limit in my 802.11 equipment at 746us beyond which I will
incur a rentransmission.

I'm prepared to wade into the code but its a fool's errand if  the latencies
will be too high to ACK within a few hundred microseconds. I'm worried that
the block latencies and USB round-trip delay would seem to make this
impossible. If anyone here can give me an informed opinion then I'll be
really happy. So, does anyone know if it is it possible to generate an ACK
within 700us or so of receiving a data frame?

Kind regards

Steve

--
The day Microsoft sells something that doesn't suck is the day they start
selling vacuum cleaners.
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