Based on reading everything I could find at Apple that seemed related, plus learning about 802.11 in some detail, I believe this is Apple's implementation of the 802.11 fallback to smaller wireless transmission frames. The idea is, the smaller the chunk of info being sent through a medium of questionable quality, the higher the liklihood of the frame being received without error. The tradeoff is slower effective speed, since each frame, no matter what size, has the same overhead. On Thu, 29 Apr 2004 VapBlack at aol.com wrote: > What does Airport Interference Robustness I have an Airport extreme card in my 1ghz TiBook I can't figure out what it does it anyone knows please tell me