[ns] new 802.11 - CAP proportion too big
Mathieu.Lacage at sophia.inria.fr
Tue Aug 15 00:12:13 PDT 2006
On Mon, 2006-08-14 at 23:54 +0100, Pedro Fortuna wrote:
> I'll do my best trying to find the problem. I'll submit a patch if I
> succeed correcting it (assuming there's a problem).
> There is a question on the DCF implementation part I'd like to ask if
> you don't mind. It seems that there's no Packet Loss. I know 802.11
> DCF MAC's is an acknowledged service with up to 7 retransmissions,
> which eliminates almost every packet loss due to transmission errors.
> But shouldn't it at least have some packet loss due to limited queue
> I have done a simulation where I create 200 nodes exchanging 400 voip
> flows and although the maximum delay is a lot higher when compared
> with a 20 or 50 node simulation, it still does not show any packet
> loss. This suggests that in your implementation you have a very long
> queue (or infinite size). Is this true? If so, In your opinion, would
> it be complicated to implement a limited queue size?
I cannot remember if the queue is size-bound or delay-bound. My curent
code (in yans) is both size and delay bound with a default size of 400
packets. The relevant code is located in mac-queue-80211.cc.
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