After playing a little bit with a topology randomly created in packet tracer, I figured out that the switch (Switch0) stores a unknown device mac address on start out, wich I think that it belongs to a indirectly connected PT-Bridge interface. (See topology) I dont know if I am right. But the Switch0 also stores the mac address interface from the other switch (Switch1) on start out. I can check it by seeing this mac address in the Switch1 interface (Fa0/1). I have not chance to verify the bridge mac addesss to argue it, and I am not sure that bridge interfaces has got mac addresses assigned. Any comment that will clear this issue will be welcome! Thanks in advance!


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1 Answer 1


Bridges learn MAC addresses from any frames they receive on an interface. Since you've connected it to a repeater hub, Switch0 learns all MACs to its north on Fa0/1.

Switches/bridges only use MAC addresses of their own for "higher" functions like management traffic, xSTP, CDP, LLDP. If Bridge0 has sent out anything like that on its west-facing port, its MAC address will show up in Switch0's MAC table. Otherwise, the MAC address belongs to one of PC0-PC7.

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