AudioCodes Mediant 500 E-SBC User Manual page 350

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Interworking SIP to ISDN overlap dialing (IP to Tel): The device sends the first
digits (e.g., "331") received from the initial SIP INVITE message to the Tel side in an
ISDN Setup message. Each time it receives additional (collected) digits for the same
dialog, which are received from subsequent SIP re-INVITE messages or SIP INFO
messages, it sends them to the Tel side in SIP Q.931 Information messages. For each
subsequent re-INVITE or SIP INFO message received, the device sends a SIP 484
"Address Incomplete" response to the IP side to maintain the current dialog session
and to receive additional digits from subsequent re-INVITE or INFO messages. You
can use the following parameters to configure overlap dialing for IP-to-Tel calls:
•
ISDNTxOverlap: Enables IP-to-Tel overlap dialing and defines how the device
receives the collected digits from the IP side - in SIP re-INVITE [1] or INFO
messages [2].
•
TimeBetweenDigits: Defines the maximum time (in seconds) that the device waits
between digits received from the IP side. When the time expires, the device uses
the collected digits to dial the called destination number.
Note: For IP-to-Tel overlap dialing, to send ISDN Setup messages without including
the Sending Complete IE, you must configure the ISDNOutCallsBehavior parameter
to USER SENDING COMPLETE [2].
For more information on the above mentioned parameters, see PSTN Parameters on page
819. For configuring ISDN overlap dialing using the Web interface, see ''Configuring Trunk
Settings'' on page 333.
User's Manual 350
Mediant 500 E-SBC
Document #: LTRT-10437