Configuring UDP Ports
The transaction-based RADIUS protocol uses two UDP ports: one for authentication packets and one for accounting packets. The ports must be configured on both sides—the Steel-Belted Radius/SPE server and the RADIUS clients (SDX application and E-series router). RADIUS client/server configuration is described later in this chapter.
The officially assigned UDP port numbers are:
Early deployments of RADIUS used 1645/udp for authentication packets and 1646/udp for accounting packets.
The (ports) section of the radius configuration file radius.ini allows you to set the UDP ports used for authentication and accounting and the UDPAuthPort and UDPAcctPort fields for port assignment. You can specify more than one port that the SPE server is listening to; for example:
If no port settings are present in the radius.ini file, the SPE server attempts to read the port numbers associated with the RADIUS servers from the /etc/services file.
If no port settings are present in the radius.ini file and no RADIUS services are defined in the /etc/services file, the SPE server listens to UDP ports 1645 and 1812 for authentication and UDP ports 1646 and 1813 for accounting.