AudioCodes Mediant 600 User Manual page 788

Parameter
Web: Play Ringback Tone to
Trunk
[PlayRBTone2Trunk_x]
User's Manual
is set to 1.
Note: This parameter is applicable to the Gateway and IP-to-IP
applications.
Determines the playing method of the ringback tone to the trunk
side per trunk.

[-1] Not configured = (Default) The settings of the
PlayRBTone2Tel parameter is used.

[0] Don't Play = When the device is configured for ISDN /
CAS, it doesn't play a ringback tone. No Progress Indicator
(PI) is sent to the ISDN unless the ProgressIndicator2ISDN_x
parameter is configured differently.

[1] Play on Local = When the device is configured for CAS, it
plays a local ringback tone to the PSTN upon receipt of a SIP
180 Ringing response (with or without SDP). Note that the
receipt of a SIP 183 response does not cause the device
configured for CAS to play a ringback tone (unless the
SIP183Behaviour parameter is set to 1).
When the device is configured for ISDN, it operates according
to the LocalISDNRBSource parameter, as follows:

If the device receives a SIP 180 Ringing response (with or
without SDP) and the LocalISDNRBSource parameter is
set to 1, it plays a ringback tone and sends an ISDN Alert
with PI = 8 (unless the ProgressIndicator2ISDN_x
parameter is configured differently).

If the LocalISDNRBSource parameter is set to 0, the
device doesn't play a ringback tone and an Alert message
without PI is sent to the ISDN. In this case, the PBX /
PSTN plays the ringback tone to the originating terminal.
Note that the receipt of a 183 response does not cause
the device to play a ringback tone; the device sends a
Progress message (unless SIP183Behaviour is set to 1). If
the SIP183Behaviour parameter is set to 1, the 183
response is handled the same way as a 180 Ringing
response.

[2] Prefer IP = Plays according to 'Early Media'. If a SIP 180
response is received and the voice channel is already open
(due to a previous 183 early media response or due to an SDP
in the current 180 response), the device configured for ISDN /
CAS doesn't play the ringback tone; PI = 8 is sent in an ISDN
Alert message (unless the ProgressIndicator2ISDN_x
parameter is configured differently).
If a 180 response is received, but the 'early media' voice
channel is not opened, the device configured for CAS plays a
ringback tone to the PSTN. The device configured for ISDN
operates according to the LocalISDNRBSource parameter:

If LocalISDNRBSource is set to 1, the device plays a
ringback tone and sends an ISDN Alert with PI = 8 to the
ISDN (unless the ProgressIndicator2ISDN_x parameter is
configured differently).

If LocalISDNRBSource is set to 0, the device doesn't play
a ringback tone. No PI is sent in the ISDN Alert message
(unless the ProgressIndicator2ISDN_x parameter is
configured differently). In this case, the PBX / PSTN plays
a ringback tone to the originating terminal. Note that the
receipt of a 183 response results in an ISDN Progress
788
Mediant 600 & Mediant 1000
Description
Document #: LTRT-83313