Which two ports are used by default when configuring RADIUS for external authentication? (Choose two.)
Which two ports are used by default when configuring RADIUS for external authentication? (Choose two.)
When configuring RADIUS for external authentication, the default ports used are 1812 and 1813. Port 1812 is used for authentication and authorization, while port 1813 is used for accounting. These ports are defined by the Internet Engineering Task Force (IETF) in RFCs 2865 and 2866. Although historically ports 1645 and 1646 were used for these purposes, the current standard ports are 1812 and 1813.
On all recent RADIUS server implementations, UDP/1812 is the authentication and authorization port, and UDP/1813 is the accouting port. However, in historic RADIUS versions, these ports were different: UDP/1645 for autentication and authorization, and UDP/1646 for accounting.
I would say A and D. The port values of 1812 for authentication and 1813 for accounting are RADIUS standard ports defined by the Internet Engineering Task Force (IETF) in RFCs 2865 and 2866. However, by default, many access servers use ports 1645 for authentication requests and 1646 for accounting requests
However, taking just authentication ports it would be 1812 and 1645, giving as correct the initial answers.