ECMP allows routers to place multiple routes in the Routing Table if they have an equal Router Metrics cost. By using ECMP, routers will Load Balancing outbound traffic between the different paths.
Note that all Interior gateway protocols (IGPs) will perform ECMP by default, but Enhanced Interior Gateway Routing Protocol (EIGRP) is the only protocol of UnEqual Cost Multi Path.
Note
Load balancing can also be achieved with static routes: simply input both routes in the table.