Which protocol and port have been assigned by IANA for RADIUS authentication?
A.
UDP/1812
B.
UDP/1813
C.
TCP/1812
D.
TCP/1813
Explanation:
Technical description for port 1812:
The RADIUS (Remote Authentication Dial-In User Service) protocol running on the system port
1812 is related to its authentication module. This service is primarily an element of a networking
protocol which allows for a deployment of centralized accounting, authorization and access
procedures. This protocol allows for the management of network resources for the efficient usage
of network services.
When a user or a device attempts to connect to a network service, the authentication process is
normally executed. The protocol using the computer port 1812 determines the appropriate user
privileges for the entered credentials. A corresponding record of the network access is recorded
into the accounting server for the implementation of the Triple A process.
The protocol supported by the network port 1812 is normally deployed by ISPs (Internet Service
Providers) due to its ubiquitous support nature.
This service also supports the implementation of VPNs (Virtual Private Networks) and wireless
networking environments.
UDP port numbers
RADIUS has been officially assigned UDP ports 1812 for RADIUS Authentication and 1813 for
RADIUS Accounting by the Internet Assigned Numbers Authority (IANA). However, prior to IANAallocation of ports 1812 and 1813, ports 1645 and 1646 (authentication and accounting,
respectively) were used unofficially and became the default ports assigned by many RADIUS
Client/Server implementations of the time. The tradition of using 1645 and 1646 for backwards
compatibility continues to this day. For this reason many RADIUS Server implementations monitor
both sets of UDP ports for RADIUS requests. Microsoft RADIUS servers default to 1812 and 1813.
Cisco RADIUS servers listen on RADIUS ports UDP 1645 and UDP 1812 for authentication; on
ports 1646 and 1813 for accounting and can be configured with non-standard ports. Juniper
Networks’ RADIUS servers listen on both unofficial and official ports 1645, 1812, 1646 and 1813
by default but can be configured with arbitrary ports.http://en.wikipedia.org/wiki/RADIUS
http://www.pc-library.com/ports/tcp-udp-port/1812/