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Spanning Tree  + Switching Loops

Last Modified: 2012-05-09
I am trying to understand bridign loops to get better understanding of spanning tree
Firstly the cisco documentation talks alot about segments to me i take it as a segment is broadcast domain so each vlan is a segment??

So for example say we have 2 vlans spread over couple of switches same user vlans 2 + 3.

Say a pc connected to one of the access ports on 1  of the switches say fa0/3 in vlan 2 on switch2 . When it sends a frame to a pc on vlan 3. Does all the access ports in vlan 2 see the frame or is just fa0/3?? Do all switch access ports see all frames in the same vlan/same segment or is just broadcast frames that all switchports will see.
The way i though it happened was that each switch learns from each source address so say the pc on fa0/3 transmits a frame the switch puts in it cam table the source mac of the pc as reachable though fa0/3

What is confusing is the bridging loops.
the example i have  has    2 segments and 2 switches a pc on 1 segment transmits to a pc on another segment why does both switches on the first segment get the frame and put in there cam table would  switch 2 not just get it as it is on the fa0/3 of the switch ?? see attachement

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