IP Trunks and national cpn prefix

[mizuno]

the issue is that when BT present an incoming call number to us, they present it without the zero - I.e. 2071234556 rather than 02071234556. Because of this, someone before my time has setup the phone system with the National CPN Prefix of 0 (which does seem to be a correct setting). At the moment, that all works fine, but when we start using IP trunks, the london site sees all internal extensions for other sites as starting with a zero - I.e. 5790 becomes 05790 etc. This does not happen over the DCS trunk.

I have contacted BT about presenting incoming cals with a 0 but they say they are unable to do this.

Any ideas how I can resolve this issue?

 

[dimas]

Hello.
Why you just don't clear National CPN Prefix in system feature- at all?
Check AAR or ARS(what you are using?) analysis tables for numbering plan format, looks like you could remove 0 from extension calling numbers if change call type to unk or aar.

 

[mizuno]

The issue is then external incoming calls appear 207 rather than 0207, it is complicated by the fact we have sbs extenions with our IP trunks, which meant we had to add entries to our public unknown numbering table, so now when you 4 digit dial over the IP trunk it thinks that number is a public number and adds the 0.

 

[dimas]

Ok. Clear for external calls.
But how you route extensions call to IP trunks ?

 

[mizuno]

in brief, our aar digit analysis table points to a route pattern, which points to the ip trunk.

 

[dimas]

Definity insert National CPN prefix if call type is national. Call type you can change in change aar analysis .... .
It seems to me you have natl, but try to change this field to pub-unk or other and may be your extensions will lose prefix 0 when call to IP trunk.

 

[mizuno]

I dont think the issue is the aar entries, its because we use sbs for failover, that we have to have the sbs extensions and the ip trunk in the public unknown numbering table thats causing the issue, as now the definity thinks that extensions dialed over ip trunk are public numbers and and adds the cpn prefix to the extension hence the 0.

 

[dimas]

Did you look at display isdn public-unkown-numbering ?
What inserted there for prefix for extension to IP trunk call?

 

[mizuno]

Yes i did, there is no cpn prefix entry for the ip trunk

 

[dimas]

Sorry, may be i cycled but very interesting what you have in aar analysis call type field?

 

[mizuno]

all call type fields are aar

 

[dimas]

I look at the Book...

Call Type Numbering Plan Identifier Type of Numbering
aar E.164(1) national(2)
intl E.164(1) international(1)
pubu E.164(1) unknown(0)
lev0 PNP(9) local(4)
lev1 PNP(9) Regional Level 1(2)
lev2 PNP(9) Regional Level 2(1)

Only for one string for test reason could you change aar call type to pubu that instruct Definity to use unkown numbering instead of national?

 

[mizuno]

thats the issue, it is using unknown numbering now, thats why it adds the cpn prefix 0 becasue it thinks ext 4123 is a public number