This document explains how to prevent the loss of dual tone multifrequency (DTMF) packet digits by reducing the Dialogic off-hook delay in Cisco Unity private branch exchange (PBX) integrations.
With some analog PBX integrations, such as Lucent/Avaya, the PBX can send DTMF signaling digits before the Dialogic card is ready to receive the digits. As a result, Cisco Unity can miss the first digit of the DTMF packet.
When an integrated call arrives, Cisco Unity may unexpectedly do one of the following:
Note: Integrated calls can be direct subscriber calls or forwarded calls.
This problem applies to Cisco Unity 2.4.0 through 3.0(2).
If possible, program the PBX to pause before sending the integration digit. Consult your PBX documentation or contact your PBX vendor for support.
If the PBX cannot be programmed to pause before sending the DTMF, reduce the Dialogic off-hook delay setting according to the procedure below. Note that this procedure applies only to systems with Dialogic voice cards and to each Dialogic card in the system.
Note: If a message displays indicating that devices could not be detected, click OK. Stop the Dialogic service using the red stop button.
Below is a sample Quiet50.prm file.
!--- QUIET50.PRM !--- Silence Threshold = -50 dBm !--- This is the Dialogic parameter file used with DNA2 for Windows NT. !--- Created on July 20, 1998 BC. !--- Original values based on parameter files. !--- last qualified with SR4.11 for OS/2 using D4X.FWL !--- version 2.70. 9/22/95 MA AREA=VOICE SIZE=WORD BASE=DECIMAL PARAM 111 : 16039 PARAM 112 : 76 PARAM 11 : 57296 !--- Playback Volume low word PARAM 12 : 43 !--- high word, set to PARAM 22 : 40201 !--- AGC window low word PARAM 23 : 2 !--- high word PARAM 42 : 62165 !--- AGC minimum average low PARAM 43 : 38264 !--- high word PARAM 44 : 45585 !--- AGC slope after attenuation PARAM 45 : 65535 !--- high word PARAM 46 : 43 !--- AGC attenuation threshold PARAM 47 : 0 !--- high word PARAM 48 : 57296 !--- Playback Volume Cap low PARAM 49 : 43 !--- high word, set to -11.5dbm PARAM 77 : 6 !--- Signal to noise ratio PARAM 67 : 18227 !--- Silence threshold low word PARAM 68 : 0 !--- Silence threshold hi word
PARAM 56 : 3 !--- Offhook Delay
Parameter 56 is the off-hook delay. In this case the parameter is set to three. This setting represents 30 milliseconds (.3 second).
Note: Parameter settings do not need to be set in numeric order.
For additional resources, refer to Cisco TAC Tools for Voice, Telephony and Messaging Technologies.
All contents are Copyright © 1992--2002 Cisco Systems, Inc. All rights reserved. Important Notices and Privacy Statement.
|Updated: Dec 12, 2002||Document ID: 5213|