How to Use Neighbor Discovery in Your Network

Neighbor discovery is the Layer 2 process in which a device identifies and advertises itself to its directly connected neighbors. Extreme Networks devices support the following neighbor discovery protocols:

• Link Layer Discovery Protocol (LLDP) and its extension, LLDP-MED, which is the IEEE 802.1AB standard for neighbor discovery
• Enterasys Discovery Protocol, for discovering Extreme Networks devices
• Cisco Discovery Protocol, for discovering Cisco devices

Neighbor discovery is useful for

• Determining an accurate physical network topology
• Creating an inventory of network devices
• Troubleshooting the network

LLDP, Enterasys Discovery Protocol, and Cisco Discovery Protocol are enabled on Extreme Networks devices by default. Though all three discovery protocols can run simultaneously, LLDP is the preferred protocol.

If a device, attached to a port that has been enabled for neighbor discovery, does not support LLDP but supports Enterasys Discovery Protocol or Cisco Discovery Protocol, then one of those protocols is used instead.