HP FlexNetwork MSR Series Configuration Manual page 341

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
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. When receiving an Authorization acknowledgment, the originating gateway
sends a VoIP_Accounting_Start request (call segment 2) to the RADIUS server.
3. After receiving a VoIP_Accounting_Start acknowledgment (call segment 2) from the RADIUS
server, the originating gateway originates a call to the terminated gateway over the IP network
so as to set up a voice channel on the IP network side. After receiving a Connect request from
Figure 105, the entire call setup process is as follows:
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