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New Member

Switch at first time

Hi all,

one small clarification,

New switch how it is learning MAC address of the hosts for the first time, whether

Sending broadcast to all hosts and receiving their MAC addresses or

When one host is trying to communicate with other host, it is adding MAC address to MAC address table?


Ramesh Kumar


Re: Switch at first time

1.First time when it receives a frame on a port, it associate the Source MAC address of that frame to the port on which frame is received.

2.Then it broadcast that frame.

3.Some other hosts replies to that frame on another port, switch associates source MAC address of that frame with the that port

So you are right when it is trying to communicate with other hosts it adds the SOURCE MAC address of that frame into mac-address-table, which you can see using

"show mac-address-table" command

HTH..rate if helpful..

New Member

Re: Switch at first time

So, initially switch will not send any broadcast to connected hosts right?

Switch will not know about any hosts and their MAC address. Is it right?