Mediant 2000 SIPMediant 2000 SIP User’s Manual 140 Document #: LTRT-725048.3 ISDN Overlap DialingOverlap dialing is a dialing scheme used by several ISDN variants to send and / or receive callednumber digits one right after the other (or several at a time). As opposed to the enbloc dialingscheme in which a complete number is sent.The Mediant 2000 can optionally support ISDN overlap dialing for incoming ISDN calls for theentire 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 theSetupAck ISDN message.The Mediant 2000 stops collecting digits (for ISDNÆIP calls) when:• The sending device transmits a "sending complete" IE in the ISDN Setup or the followingInfo messages to signal that no more digits are going to be sent.• The inter-digit timeout (configured by the parameter ‘TimeBetweenDigits’) expires. Thedefault for this timeout is 4 seconds.• The maximum allowed number of digits (configured by the parameter ‘MaxDigits’) isreached. The default is 30 digits.Relevant parameters (described in Table 6-6 on page 122):• ISDNRxOverlap• ISDNRxOverlap_x• TimeBetweenDigits• MaxDigits• ISDNInCallsBehavior
