Nortel Networks TP-1610 SIP user manual Isdn Overlap Dialing

Mediant 2000 SIP

8.3ISDN Overlap Dialing

Overlap dialing is a dialing scheme used by several ISDN variants to send and / or receive called number digits one right after the other (or several at a time). As opposed to the enbloc dialing scheme in which a complete number is sent.

The Mediant 2000 can optionally support ISDN overlap dialing for incoming ISDN calls for the entire gateway by setting ‘ISDNRxOverlap’ to 1, or per E1/T1 span by setting ‘ISDNRxOverlap_x’ to 1 (‘x’ represents the number of the trunk, 0 to 7).

To play a Dial tone to the ISDN user side when an empty called number is received, set ‘ISDNINCallsBehavior = 65536’ (bit #16) causing the Progress Indicator to be included in the SetupAck ISDN message.

The Mediant 2000 stops collecting digits (for ISDN IP calls) when:

•The sending device transmits a "sending complete" IE in the ISDN Setup or the following Info messages to signal that no more digits are going to be sent.

•The inter-digit timeout (configured by the parameter ‘TimeBetweenDigits’) expires. The default for this timeout is 4 seconds.

•The maximum allowed number of digits (configured by the parameter ‘MaxDigits’) is reached. The default is 30 digits.

Relevant parameters (described in Table 6-6on page 122):

•ISDNRxOverlap

•ISDNRxOverlap_x

•TimeBetweenDigits

•MaxDigits

•ISDNInCallsBehavior

Mediant 2000 SIP User’s Manual 140 Document #: LTRT-72504