Refer to the exhibit. Look at the command output. What would be the most probable reason for
this port-ID mismatch?

A.
spanning-tree misconfiguration

B.
speed mismatch configuration

C.
cabling problem

D.
configuration problem

Explanation:
As CDP has different information for Switch1 it is obvious that there is a cabling issue
Verifying Layer 2 Connectivity
Verifying Layer 2 connectivity involves checking switch ports and each connected device at an
Ethernet level, ensuring Layer 2 connectivity has been established and also checking errors for a
connection. Although all indications might be that a Layer 2 connection is operational, it is also
good to actually confirm that Layer 2 traffic is being sent and received between two devices. Cisco
Discovery Protocol (CDP) provides such functionality, verifying connectivity to locally connected
Cisco devices.
Checking Network Cabling
Many physical layer connectivity problems are caused by faulty network cabling. All cabling
between your switch and the rest of the network should be thoroughly tested prior to
implementation using a professional cable tester. Ensure that you always use compatible cables
for the protocol you are using.
A common source of cabling issue is the incorrect use of straight-thru and crossover RJ-45 cables.
Any device to-switch connection should use a straight-thru RJ-45 cable, while any device-todevice or switch-to-switch connection requires the use of a crossover RJ-45 cable.