AudioCodes Mediant 3000 User Manual page 699

User's Manual
Parameter
Web/EMS: Enable Early
183
[EnableEarly183]
[IgnoreAlertAfterEarlyM
edia]
Version 6.6
the call.

[0] Disable (default)

[1] Enable
The inclusion of the SDP in the 18x response depends on the ISDN
Progress Indicator (PI). The SDP is sent only if PI is set to 1 or 8 in the
received Proceeding, Alerting, or Progress PRI messages. See also the
ProgressIndicator2IP parameter, which if set to 1 or 8, the device
behaves as if it received the ISDN messages with the PI.

For the CAS protocol: See the ProgressIndicator2IP parameter.

For the ISDN protocol: Sending a 183 response depends on the
ISDN PI. It is sent only if PI is set to 1 or 8 in the received
Proceeding or Alerting PRI messages. Sending 183 response also
depends on the ReleaseIP2ISDNCallOnProgressWithCause
parameter, which must be set to any value except 2.
Notes:

See also the IgnoreAlertAfterEarlyMedia parameter. This parameter
allows, for example, to interwork Alert + PI to SIP 183 + SDP instead
of 180 + SDP.

You can also configure early SIP 183 response immediately upon
receipt of an INVITE, using the EnableEarly183 parameter.

This feature can also be configured as an IP Profile and/or Tel
Profile.

This parameter is applicable only to the Gateway/IP-to-IP
application.
Enables the device to send SIP 183 responses with SDP to the IP upon
receipt of INVITE messages. This parameter is applicable to IP-to-Tel
(ISDN) and IP-to-IP calls, and applies to all calls.

[0] Disable (default)

[1] Enable

IP-to-Tel calls: By sending the 183 response, the device opens
an RTP channel before receiving the "progress" tone from the
ISDN side. The device sends RTP packets immediately upon
receipt of an ISDN Progress, Alerting with Progress indicator, or
Connect message according to the initial negotiation without
sending the 183 response again, thereby saving response time
and avoiding early media clipping.

IP-to-IP calls: Sending the 183 response enables SIP servers
that require a stream of early media, to keep sessions open.
Notes:

To enable this feature, set the EnableEarlyMedia parameter to 1.

When the BChannelNegotiation parameter is set to a non-Exclusive
value (Preferred or Any), the EnableEarly183 parameter is ignored
and a SIP 183 is not sent upon receipt of an INVITE. In such a case,
you can set the ProgressIndicator2IP parameter to 1 (PI = 1) for the
device to send a SIP 183 upon receipt of an ISDN Call Proceeding
message.

This feature can also be configured in an IP Profile.
Determines the device's interworking of Alerting messages from PRI to
SIP.

[0] = Disabled (default)

[1] = Enabled
699
53. Configuration Parameters Reference
Description
Mediant 3000