Which authentication protocol would be MOST appropriate to complement RADIUS for a secure remote access solution?

In the context of enhancing RADIUS for secure remote access, selecting the most appropriate authentication protocol is essential. PEAP (Protected Extensible Authentication Protocol) is particularly suitable because it provides an additional layer of security by encapsulating a second authentication protocol within a secure TLS tunnel.

PEAP operates by first establishing a secure, encrypted tunnel using TLS. This protects the user credentials and authentication process from being transmitted in clear text over the network, which is critical in remote access scenarios where threats like eavesdropping are present. Once this secure tunnel is established, it allows for the authentication of users without exposing sensitive data.

This characteristic of PEAP makes it effective at mitigating certain vulnerabilities associated with sending credentials directly over the network, which can happen with other protocols that don't establish such a secure tunnel. By utilizing PEAP alongside RADIUS, organizations can ensure that both user authentication and data transmission remain protected, creating a robust solution for secure remote access.

In contrast, while protocols like EAP-TLS also provide high levels of security through mutual authentication using digital certificates, they require a more complex implementation and management of certificate infrastructure. MS-CHAPv2, on the other hand, suffers from known vulnerabilities and does not provide the same level of protection as PEAP