On Sun, 18 Nov 2001, Mike Bresnahan wrote: > Could someone explain to me in a nutshell how 10mb and 100mb co-exist > happily on the same ethernet? I haven't read all my e-mail yet, but in a nutshell here's how a switch works: You have 2 10Bt ethernet in ports 1 and 2. You have 2 100Bt ethernet in ports 3 and 4. If port 4 wants to transfer a file to port 3, it negotiates at the highest possible speed on the send (100 Mb). If port 2 wants to send to port 1, it negotiates at 10 Mb. The nice thing about a switch is that even if you're doing a massive transfer between ports 1 and 2, ports 3 and 4 are sitting idle. You can move files between 3 and 4/2 and 1 simultaneously. Hope that helps. -Brian