Which statement is true about CDP on a Cisco device?
- The show cdp neighbor detail command will reveal the IP address of a neighbor only if there is Layer 3 connectivity.
- To disable CDP globally, the no cdp enable command in interface configuration mode must be used.
- CDP can be disabled globally or on a specific interface.
- Because it runs at the data link layer, the CDP protocol can only be implemented in switches.
CDP is a Cisco-proprietary protocol that can be disabled globally by using the no cdp run global configuration command, or disabled on a specific interface, by using the no cdp enable interface configuration command. Because CDP operates at the data link layer, two or more Cisco network devices, such as routers can learn about each other even if Layer 3 connectivity does not exist. The show cdp neighbors detail command reveals the IP address of a neighboring device regardless of whether you can ping the neighbor.