Description: Unequal cost load balancing is a feature of the EIGRP (Enhanced Interior Gateway Routing Protocol) that allows traffic to be distributed across multiple routes with different associated costs. Unlike other routing protocols that may choose the lowest-cost route, EIGRP enables traffic to be directed through several routes simultaneously, even if these routes have unequal costs. This is achieved through the use of an algorithm that evaluates the metrics of each route, such as bandwidth, latency, and load, to determine how traffic should be distributed. This capability is particularly useful in networks where maximizing resource usage and improving traffic efficiency is desired. Unequal cost load balancing not only optimizes network performance but also provides redundancy, meaning that if one route fails, traffic can be redirected through the remaining routes without service interruption. In summary, this feature of EIGRP allows for more flexible and efficient traffic management, adapting to the changing conditions of the network infrastructure.
History: EIGRP was developed by Cisco in 1993 as an enhancement of the IGRP (Interior Gateway Routing Protocol). The introduction of unequal cost load balancing was one of the key features that set EIGRP apart from other routing protocols at the time. Over the years, EIGRP has evolved and become a de facto standard in many enterprise networks due to its ability to handle complex networks and its efficiency in traffic management.
Uses: Unequal cost load balancing is primarily used in enterprise networks where efficient traffic management is required. It allows network administrators to optimize the use of multiple network links, improving responsiveness and service availability. This feature is especially valuable in environments where redundancy and fault tolerance are critical.
Examples: A practical example of unequal cost load balancing could be a network that has two links to the same destination: one with a cost of 100 and another with a cost of 200. EIGRP can send traffic in proportion to the associated costs, thus maximizing the use of both links.
