Which type of authentication does EIGRP support?

EIGRP (Enhanced Interior Gateway Routing Protocol) supports both MD5 and SHA authentication methods, which provides enhanced security in routing updates between EIGRP routers. MD5 is the most commonly used authentication method for EIGRP and it has been supported since the protocol was introduced. It helps in ensuring the integrity and authenticity of routing information exchanged between routers.

With the existence of SHA, EIGRP can further offer strengthened secure authentication options for environments that require higher security. Implementing either authentication method is crucial for preventing unauthorized routers from participating in the EIGRP routing domain and mitigating potential network attacks such as routing table poisoning.

Options indicating a singular authentication method (either SHA only or MD5 only) overlook the availability of both methods for different security needs. Additionally, the assertion that no authentication is supported incorrectly assumes that EIGRP operates without any security measures, which it does not; securing routing updates is essential for maintaining the stability and trustworthiness of the network. Therefore, recognizing that EIGRP offers both MD5 and SHA authentication options is key to effectively implementing and securing EIGRP in a network.