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

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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 the originating
gateway, the terminating gateway sends a VoIP_Accounting_Start request (call segment 3) to the
RADIUS server.
4. After receiving a VoIP_Accounting_Start acknowledgment (call segment 3) from the RADIUS server,
the terminating gateway originates a call to the called party over PSTN. After receiving an Alert
from PSTN, the terminating gateway sends a Notification to the originating gateway and the
originating gateway then plays ringback tones to the calling party.
5. After the called party picks up the phone, the terminating gateway sends a
PSTN_Accounting_Start request (call segment 4) to the RADIUS server. After the terminating
gateway receives a PSTN_Accounting_Start acknowledgment (call segment 4) from the RADIUS
server, both parties start a conversation.
6. After the call is connected, the originating gateway sets the call duration timer according to the call
duration in the Authorization acknowledgment. When the calling or called party hangs up before
the timer expires, the call is normally disconnected.
7. If the calling party hangs up first, the originating gateway releases the seized voice subscriber line
and sends a VoIP_Accounting_Stop request to the RADIUS server (call segment 2) and a
Voice_Channel_Release to the terminating gateway, and then sends a PSTN_Accounting_Stop
request to the RADIUS server (call segment 1). After receiving the Voice_Channel_Release, the
terminating gateway releases the channel resource, and sends a PSTN_Accounting_Stop request
(call segment 4) and a VoIP_Accounting_Stop request (call segment 3) to the RADIUS server.
In the above call setup process, accounting is divided into four segments to facilitate charge settlement
between service providers as well as control of voice channel by segment.
The call setup process and call clearing process are briefly described here. In practice, the call setup
process and messages exchanged differ greatly, because message exchange in the entire process is
quite complicated, access procedures differ, AAA fails, calls are exceptionally terminated, or the called
party hangs up.
Obviously, RADIUS cannot operate correctly without the RADIUS server. AAA messages exchanged
between the voice gateway and the RADIUS server should comply with RFC 2865 and RFC 2866. A list
of voice call users of the voice gateway should also be configured on the RADIUS server.
RADIUS provided by voice gateway
AAA for voice calls
For voice calls, the RADIUS authentication includes card number/password authentication and calling
number authentication. The RADIUS authorization adopts the called number authorization mode on
condition that the RADIUS authentication is enabled.
For voice calls, the voice gateway supports three accounting methods: start-ack, start-no-ack, and
stop-only.
• start-ack—When the call setup begins, the voice gateway sends an Accounting-Start request to the
RADIUS server. However, the voice gateway must receive an Accounting_Start acknowledgment
from the RADIUS server before connecting the call. After the call ends, the voice gateway sends an