What is the administrative distance (AD) used by EIGRP?

The administrative distance (AD) is a value used by routers to determine the trustworthiness of routes from different protocols. For EIGRP (Enhanced Interior Gateway Routing Protocol), the standard administrative distance is set at 90. This low value indicates that EIGRP is considered highly reliable and trustworthy compared to other routing protocols.

In the context of routing protocols, a lower AD value signifies a higher priority when it comes to route selection. EIGRP's AD reflects its advanced features, which include fast convergence and support for both classful and classless routing, making it a popular choice in various environments.

Understanding the AD values of different protocols is crucial when designing networks, as it helps in making informed decisions about which protocols to implement based on their reliability and performance characteristics.