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How does GBIC and STP work ?

For trunks,

I know that when you connect 2 switches together via regular ports you need 2 ports connected on both switches via crossover. Then STP blocks one of the ports on the non-root bridge.

I also know that you can setup etherchannel so that STP sees both ports on each switch as one.

My question is if I connect both switches via single GBIC modules, how does STP work ? Do I need to use 2 GBIC modules on each switch connected to eachother ?

Also, if I'm using newer switches like 3550 and 3750, then I do not need to use a crossover cable for trunks between switches, correct ?


Re: GBIC and STP

STP is used to avoid the loop in the redundant if you are going to have only one connection between two switch then you do not need to worry about the loop...

yes if you have redundant connection between switch then you need to look for the loop at that time STP will come into the picture ...

look at this link for operation of STP :

if you are going to connect two switch then you need to have cross cable...or your switch must be support to auto-MDIX future if you want to use stright cable...

and stp will work same for all connectivity...

hope this will help you

rate this post if it helps