My comments are based on some tests that I ran a couple of weeks ago. Latency between Stanford and MIT via the T3 NSFnet was much greater than an equivalent path via CIX/Alternet (about 50% longer delay via the NSFnet). The results were repeatable and consistent. Throughput was also lower but I attribute that to the longer latency and limited TCP window size. The bottom line was that the performance as seen by a standard workstation using standard networking tools was better via CIX. I suspect that very large windows would push the throughput performance in favor of the NSFnet but I do not have the tools right now to test that. Anybody have a TCP with large windows I can play with? Brian Lloyd, WB6RQN Lloyd & Associates Principal and Network Architect 3420 Sudbury Road brian@lloyd.com Cameron Park, CA 95682 voice (916) 676-1147 -or- (415) 725-1392