yes.

There might be manufacturers differences in how data is buffered in the switch, and how fast the switch actually works, but ethernet links do not change speed dynamically. ( they can auto-detect the speed of the connection - but once connected they do not switch speeds to accomodate different speed links on the switch. )

http://www.microsoft.com/technet/sec.../secmod40.mspx

a single chip design might look something like this.

http://edevice.fujitsu.com/fj/MARCOM...-4e/pdf/36.pdf

this is a manufacturers ethernet chip datasheet

http://www.amd.com/us-en/assets/cont...docs/22925.pdf