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Same source and destination MAC address

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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

ssp
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One Answer:

1

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

http://www.cisco.com/image/gif/paws/10607/lan-switch-transparent.swf

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 ♦