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Same source and destination MAC address


What will the Ethernet switch do, if my NIC transmits an Ethernet frame with same source and destination MAC address?

asked 14 Feb '13, 04:01

ssp's gravatar image

accept rate: 0%

One Answer:


Normally a switch will never forward a packet out a port on which it was received, whether it was destined for the same mac address or not.

answered 14 Feb '13, 09:02

SYN-bit's gravatar image

SYN-bit ♦♦
accept rate: 20%

There is a nice flash video (hosted on - apparently from that shows the working of a switch, including filtering. The setup is slightly different but still the same 'problem'.

Maybe that helps the OP to better understand...

BTW: Works will in IE not so well in Firefox !?!

(18 Feb '13, 09:06) Kurt Knochner ♦