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Sluggish WiFi Connections Hurt Everyone
MindNumbingOblivion writes "Wireless technology has revolutionized access to local area networks when one can't always be close to an ethernet jack. But a recent research paper from the French Centre Nationale de la Recherche Scientifique tells how one slow user accessing a hot point can hurt the whole group. Apparently the very nature of CSMA/CD guarantees such anomalies. Here's the story, and here's the release from CNRS (in French)."
Those with 802.11b cards that handle 11Mbps should not complain too loudly about those that connect at only 1Mbps. The 11Mbps connections slow faster wireless networks down to their speed.
802.11g is supposed to be both 54Mbps and backwards compatible to 802.11b. From my own experience with 802.11g, if there is even one person using an 11Mbps connection, the rest of the wireless nodes also slow down.
Just like driving on a one lane country highway behind a slow car doing only 11 mph in a 54 mph zone.
Unfortunately, RTS/CTS is almost worthless in a situation that requires it - when you've got hidden nodes, the RTS mechanism can just as easily cause collisions.
The users of WAFreeNet (Perth, Australia) have just released some open source software (frottle) to combat this. Essentially it provides a polled/token operation at the IP layer, virtually eliminating collisions. This is a similar application to WiCCP, and we've been helping/competeing with the WiCCP developers. The other alternative is Karlnet Turbocell - expensive proprietarty software, firmware and hardware, with poor linux support.
I cant post any url's now - the websites wouldnt appreciate the slashdotting. For those of you than can find the sites for yourself, it may be well worth your time.