At which layer of the OSI model does the protocol that provides the information that is displayed
by the show cdp neighbors command operate?

A.
application

B.
transport

C.
network

D.
physical

E.
data link

Explanation:
CDP is a device discovery protocol that runs over Layer 2 (the data link layer) on all Ciscomanufactured devices (routers, bridges, access servers, and switches) and allows network
management applications to discover Cisco devices that are neighbors of already known devices.
With CDP, network management applications can learn the device type and the Simple Network
Management Protocol (SNMP) agent address of neighboring devices running lower-layer,
transparent protocols.