On Fri, Jan 11, 2008 at 10:03:41AM -0800, johnny wrote: > The graphs say it is clearly not bandwith fault. Reading around: > " It is well known > that the medium access control (MAC) layer is the main bottleneck for > the IEEE 802.11 wireless LANs." In particular, the hidden transmitter problem really bites 802.11b/g. If computer A , Computer B, and access point P can "see" each other, things work better. If A and B can see P, but not each other, problems arise. A starts transmitting. B doesn't see A, and also starts transmitting. P gets junk because there are overlapping transmissions. Neither A nor B see the collision, and have to wait for a timeout before retrying. This is a large window, because B could start transmitting any time during A's packet.
This is also a problem when A can see B, and they start transmitting at the "same" time, but these occurrences are less frequent since the window is much smaller. -- Rob
signature.asc
Description: Digital signature
