Cisco CCNA mock exam questions sample test – Question 38

.In the diagram below, if the workstation at sends a packet to the workstation at, what will be the source physical address when the packet arrives at


A. ab.ab.ab.ab.ab.ab
C. dd.dd.dd.dd.dd.dd
E. aa.aa.aa.aa.aa.aa

Correct Answer
: C

The source physical address of the packet when it arrives at will be that of the interface on the R2 router, dd.dd.dd.dd.dd.dd . Each router will change the MAC address field to the MAC address of its sending interface as it sends the packet and will leave the IP address field unchanged. The switches will change neither field, but will simply use the MAC address field to determine the forwarding path and switch the frame to the port where the MAC address is located. The R2 router is the last device that will make a change to the MAC address field.
The source ( and destination ( IP address fields will stay the same at each device. The MAC address field changes when R1 sends the frame to R2 and when R2 send the frame to the workstation at

LAN Switching Fundamentals
Describe and verify switching concepts
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