Dialogic IMG - E1 R2 calls fail with a timeout waiting for the Calling Party Number
Symptoms:
Inbound R2 calls timeout waiting for all the digits. Call setup time is over 20 seconds to collect all of the inbound R2 digits.
Reason for the issue:
This issue may occur when the called number is variable length and the originating switch is not able to handle the BWD R2 digit transition on the inter digit timeout. In this case a BWD1 is transmitted to request more called number digits. When the inter digit timer expires a BWD5 is sent. The BWD5 notifies the originating switch to send the category digit followed by the ANI.
In some cases the originating switch may not recognize the the second BWD digit being together, and never transmitts the CAT + ANI. This causes the Dialogic IMG Integrated Media Gateway (IMG) to timeout waiting for the rest of the digits and, depending on routing requirements, the IMG may either reject the inbound call or route the call with no ANI.
Fix / Solution:
Modify the existing R2 configuration to use 4 stages with the following changes:
In Dialogic ClientView select the R2 variant and make the following changes.
a. Modify Inpulsing parameters stage 1.
i. Delete Inpulsing parameters stage 1.
ii. Add Inpulsing parameters stage 1 and set the following.
# of Digit String = 1
Time Out = 10000 (10 seconds)
Collection Method = Fixed Number of digits.
Digit Count = 2
b. Add Inpulsing parameters stage 3
i. Add Inpulsing parameters stage 3 and set the following.
# of Digit String = 1
Time Out = 10000
Collection Method = Compelled.
Digit Count = Forward R2
c. Add Inseize instruction: Receive stage 3.
d. Modify the Digit mapping for the Called Party Number for "Stage 1 - String 1" & "Stage 3 - String 1".
Move the new Inpulsing parameter and Inseize instruction up in the list so they are in the correct order.
In ClientView, select an object outside the R2 variant which will download the changes made to the IMG.
Workaround:
Have the R2 carrier send FWD 15 as a terminating digit in the called number if possible.
Product List
Dialogic IMG Integrated Media Gateway
Glossary of Acronyms / Terms
CAS - Channel Assosiated Signaling.