R2511-HP MSR Router Series Voice Configuration Guide(V5)

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Configuring voice RADIUS
Remote authentication dial-in user service (RADIUS) is a protocol standard developed for implementing
authentication, authorization and accounting (AAA) for access users, who can be PPP users or voice
users. The voice RADIUS function provided by the voice gateway (RADIUS client) is suitable for small- and
medium-sized network operators or enterprises to control voice calls and perform voice call accounting
statistics.
As a whole, voice RADIUS is a part of the whole voice module that implements AAA for voices users on
the voice gateway. When a user initiates a voice call, the voice gateway interacts with the user according
to the configured parameters, encapsulates the obtained user information and statistics into RADIUS
AAA messages, and sends the messages to the RADIUS server. The voice gateway then determines
whether to connect the call according to the response. After the call ends, the voice gateway reports to
the RADIUS server the statistics (such as call duration, number of messages, and number of bytes) about
the call to complete call accounting and other operations.
Voice RADIUS call setup process
Figure 105 shows the networking environment where voice RADIUS is applied.
Figure 105 Network diagram
As shown in Figure 105, the entire call setup process is as follows:
1. The calling party (1000) who originates a call from PSTN dials the called number 1001. The
originating gateway receives the called number and determines that the called party is not located
in the local PBX. At this point, the voice subscriber line of the originating gateway is located on the
calling side, and therefore, the originating gateway sends a PSTN_Accounting_Start request (call
segment 1) to the RADIUS server.
2. After receiving a PSTN_Accounting_Start acknowledgment from the RADIUS server, the
originating gateway obtains the identity information of the calling party, encapsulates it into a
RADIUS message, and sends the message to the RADIUS server for identity authentication. Upon
receiving an Authentication acknowledgment, the originating gateway encapsulates the called
number into another RADIUS message and sends it to the RADIUS server again for authorization.