Ccna certification Practice Tests

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 182.  B.  Switches learn MAC addresses by inspecting the frame’s source MAC address on the 

incoming port. They then associate the source MAC address with the port it came in 

on. The destination MAC address is what the forward/filter decisions are based upon. 

Spanning Tree Protocol (STP) listens and learns Bridge Protocol Data Units (BPDUs) so it 

can detect loops or potential loops. Frame type learning is not a real concept; therefore, it 

is an invalid answer.

 183.  A.  Computer A will no longer forward traffic because the static entry will override a 

dynamic entry. Computer A’s frames will not be forwarded to port Fa0/4, only Fa0/1, 

because of the static entry. Computer B’s frames will not be forwarded to all ports because 

computer B’s MAC address will be learned on Fa0/1 along with the static entry.

 184.  C.  Computer A’s frames will be forwarded to its new port of Fa0/3 since the entries will 

be cleared out when the cables are disconnected and relearned. When Computer A is 

disconnected from Fa0/2, the MAC address entries for that port will be cleared from the 

table. Therefore, frames will no longer be forwarded to Fa0/2 on behalf of Computer A, 

only to Computer A’s new port of Fa0/3. Frames are only forwarded to all active ports 

when the destination MAC address in a frame is not in the MAC address table.