PSTN to IP calls - what is the order ?

[rwawrig]

Hi

I have one little question:

when a call is going from PSTN to IP (through an AS5xxx voice gw), the call is going through a voice-port configuration, optionally can go through a "dummy" pots dialpeer - so aplications (tcl scripts can be applied for authentication or whatever), and in the end is going through a voip dialpeer out to an IP.

Until now i thought this is the order a call is taking, but after today's tests, i think the call is hitting first the "dummy" pots dialpeer, then is going through voice-port config, and after this is taking the voip dialpeer and is going out.

It is like this or i'm mistaken ?

In the other case - IP to PSTN, the order is the same ?

Thanks

Robert

[fchaudhr]

Dial-peer (i.e dial-peer voice pots) matching for inbound calls from PSTN takes the following order:

1) Match the DNIS with incoming-called #

2) match the CLI with answer-address

3) match the CLI with destination-pattern

4) use the 1st dial-peer with corresponding voice-port

See below URLs for more details:

http://cco/en/US/tech/tk652/tk90/technologies_tech_note09186a008010fed1.shtml

http://cco/en/US/tech/tk652/tk653/technologies_tech_note09186a00801142f8.shtml

[rwawrig]

Hi,

Thanks for your answer.

I know about this - what is matched when the call is reaching cisco. My question is what is happening next ? After the first dialpeer is matched, where the call is going ?

I did the following:

A call was coming from pstn with 00 in front.

I have configured a translation rule in voice-port to add 7777 in front of the number. Then i had a pots dialpeer with incoming-called number 7777T, with an application to authenticate the number and in the end i had a voip dial-peer to send the number to an IP.

The idea is that when the call was reaching cisco,, it was not translated first, and not hitting the pots dialpeer. I changed the incoming called number to 00T, and then the call was matching the dialpeer. The application was sending the called and calling number to raduis for authentication, but the called number had the 7777 prefix added.

Here i was confused: the call matched the dialpeer with incoming-called number 00T, but the application from this dialpeer sent the number to radius with 7777 prefix in front, prefix which is added by a translation rule configured in voice-port...

[fchaudhr]

1) Prior to 12.2(11)T, number translation for incoming call is done AFTER dial-peer matching. So number translation is performed and your Radius records will show 7777 prefixed to the number.

2) In 12.2(11)T Carrier Based Routing Feature on IOS changes that and number translation will be performed first and then inbound dial-peer matching is done. See Figure 1:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t11/ftgwrepg.htm