Enhanced Interior Gateway Routing Protocol (EIGRP)

Definition - What does Enhanced Interior Gateway Routing Protocol (EIGRP) mean?

Enhanced Interior Gateway Routing Protocol (EIGRP) is an advanced distance vector routing protocol based on the principles of the Interior Gateway Routing Protocol (IGRP).

Enhanced Interior Gateway Routing Protocol (EIGRP) is a successor to the Interior Gateway Routing Protocol (IGRP). Both are owned by Cisco and they operate only on their devices. Cisco introduced EIGRP because it needed a protocol with faster converging abilities, route selection and calculation and last but not the least the ability to record information from neighboring devices.

Techopedia explains Enhanced Interior Gateway Routing Protocol (EIGRP)

EIGRP has the following characteristics:

  1. Advanced operational efficiency
  2. Capabilities of both link state and distance vector
  3. A classless routing protocol
  4. Unique features including: use of Reliable Transport Protocol (RTP), a diffusing update algorithm (DUAL), updates and updated information about neighbors
  5. Faster converging because it pre-calculates routes and does not broadcast hold-down timer packets before converging

EIGRP uses bandwidth, delay, load and reliability to calculate the metric for its routing table (not hop count, which legacy protocols use). For this reason, EIGRP always selects and calculates the most optimal route for efficiency. EIGRP uses a DUAL algorithm to avoid loops and send occasional hello packets to check the status of neighbor routers.

Popular White Papers

Techopedia Newsletter Sign-Up

Get Techopedia delivered to your inbox!