Delay in Dialing extentions after conversion from 4-to-5-digits

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Apr 29th, 2009
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We have a CCM Setup with 4 digits extensions which we converted to 5-digits extentions due to customer requirement. The customer also wanted the 4-digit and 5-digit extention co-existentfor some time, so that the callers calling 4-digit can also reach new 5-digits extentions.Voice Gateways use MGCP.

Following steps were followed:

1.Modified existing translation rule to convert incoming calls look for 5 digits IP Phones extn(instead of earlier 4-digits).

2.Added translation rule to convert 4-digit extentions to 5-digits for people dialing internally(in case caller still dials 4-digit extension).

3.Already converted all existing IP Phone 4-digit extentions to 5-digits.

Now we get a delay on dialing 4-gits extentions(as I believe the CCM waits for interdigit timeout), unlike earlier when there was no delay.

Can somebody suggest to get RID of this delay, with both 4 & 5 digit extension co-existing.


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bretjaquish@hot... Wed, 04/29/2009 - 07:22
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There are two ways that I can think of:

Prevent digit overlap between 4 and 5 digit extensions. I think you can control this by use of Partitions and Calling search spaces. Are the 4 and 5 digit extensions in the same partition?

Have the users use the # sign after they dial 4 digit extensions.

Jaime Valencia Wed, 04/29/2009 - 07:25
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the only way is to have a unique dial plan and do not have overlapping extensions. OR use CSS and partitions to only reach 4 digits or 5 digits but not both.

if you don't, it's expected and documented that it will happen so the system is Working As Designed

you can only try to lower the T_302 IDT value

it's all explained in the SRND dial plan chapter.



if this helps, please rate


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