EIGRP Enhanced Interior Gateway Routing Protocol

EIGRP Enhanced Interior Gateway Routing Protocol


EIGRP Enhanced Interior Gateway Routing Protocol

Enhanced Interior Gateway Routing Protocol (EIGRP) is a Cisco proprietary protocol.

Multiple paths to destination.
Cisco proprietary protocol that is Work only with Cisco Router
Supports IP, IPX, Appletalk.
Multiple autonomous systems in same router.
AD is 90.
Route is ‘D’.
classless routing , distance vector protocol
communicates with other routers via, RTP ( Reliable Transport Protocol )
selects the best path via Diffusing update algorithm ( DUAL )
Supports multiple autonomous system on a single router
Supports VLSM and summarization
Metric – bandwidth, delay ,load and reliability
Used in large network
Multiple network layer protocol
Max hop count is 255 (100 by default)
Hello packets are send in every 5 seconds

Each EIGRP router uses three tables to store routing information:

Neighbor table – stores information about EIGRP neighbors
Topology table – stores routing information learned from neighbor routing tables.
Routing table – stores only the best routes to reach a remote network.

Some Terminology used in EIGRP.

DUAL ( Diffused Update Algorithm) this is a algorithm used for calculating the shortest path.

Neighbor table : EIGRP use hello packets to discover neighbors. It contains neighbor’s address and the interface through which it can be reached in .

Topology table : each router stores its neighbors routing tables in its EIGRP topology table

Successor is a neighboring router that has a least-cost path to a destination

Feasible successor is the next-hop router for a backup path.

Routing table contains all of the successor routes from the topology table.

Advertised distance is the distance between a neighbouring router to the specific router.

Feasible distance is the  best route to reach a destination network.


Enhanced Interior Gateway Routing Protocol (EIGRP)

Enhanced Interior Gateway Routing Protocol (EIGRP)

considering we have configure Hostname and IP address in Router01,Router03,Router03
Please refer how to configure Hostname and IP address in Router01,Router03,Router03 by clicking here.

Enhanced Interior Gateway Routing Protocol (EIGRP) configuration in Router01

Enhanced Interior Gateway Routing Protocol (EIGRP) configuration in Router02

Enhanced Interior Gateway Routing Protocol (EIGRP) configuration in Router03

view the routing table in Router01

view the routing table in Router02

view the routing table in Router03

Verify the connectivity between networks using the ping command

Now we can run ping from Host01 (IP address: 172.16.0.10/16) to Host03 (IP address: 172.20.0.10/16) for verification.

The ping reply from Host03 (IP address: 172.20.0.10/16) shows that the Enhanced Interior Gateway Routing Protocol (EIGRP) Protocol is configured well in three routers and there is network connectivity between different networks.



You May Also Enjoy Reading This …