Windows Vista, and next week Mac OS X Leopard introduced a significant improvement to the TCP stack, Window Auto-Tuning. FreeBSD is committing TCP Socket Buffer Auto-Sizing in FreeBSD 7. I've also been told similar features are in the 2.6 Kernel used by several popular Linux distributions. Today a large number of consumer / web server combinations are limited to a 32k window size, which on a 60ms link across the country limits the speed of a single TCP connection to 533kbytes/sec, or 4.2Mbits/sec. Users with 6 and 8 MBps broadband connections can't even fill their pipe on a software download. With these improvements in both clients and servers soon these systems may auto-tune to fill 100Mbps (or larger) pipes. Related to our current discussion of bittorrent clients as much as they are "unfair" by trying to use the entire pipe, will these auto-tuning improvements create the same situation? -- Leo Bicknell - bicknell@ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/ Read TMBG List - tmbg-list-request@tmbg.org, www.tmbg.org