Explain the Term EIGRP load balancing?

Load balancing is when a router is able to distribute traffic over all the router network ports that have the same distance to the destination address. It also increases network segments utilization and improves network bandwidth.

This is defined as the standard functionality of CISCO IOS router software that is in all router platforms. Load balancing is a feature built into Cisco routers that allow to share a load of traffic across multiple links and not only links that have the same cost values. EIGRP allows to make full use of redundant links that are in place for back up but are not in use and they cost a lot of money. EIGRP makes it easier for network engineers to make it happen. Load balancing is inherent to the forwarding process in the router and it is automatically activated if the routing table has multiple paths to a destination.

There are two types of load balancing as follows:

Equal Cost path

EIGRP supports equal-cost balancing over four links by default. Equal-cost balance means that multiple routes will have the same metric or cost to reach a destination. Then the router will choose to load balance across equal cost links.

All the above routers are running EIGRP protocol. Routers R2, R3 and R4 are connected to the subnet 10.10.10.0/24. The routers above advertise the route to reach subnet to R1. R1 gets updates for R2, R3 andR4 for the subnet 10.10.10.0/24 and all of them have the same metric of 20kbps. R1 places all the routes in the routing table and load balances across all the links.

Unequal Cost Load Balancing

EIGRP is the only protocol that does Unequal cost load Balancing. For example, if a network has two routers with 50kbps and 100kbps the unequal load balancing can be enabled. This happens when the links that are twice as bad as the primary.