Pri configuration for Voip

Unanswered Question
Nov 21st, 2007

hi guys, we are taking an E1 pri line which will be connected to our 2811 router. we need this PRI to forward call to PSTN when the call doesnt belong to our own network, so keeping this task in mind can somebody refer me a configuration of PRI ?? i think to forward calls to PSTN i just need to define a dial-peer, but to provide communication between router and PRI what configuration is needeD ??? i will appreciate if u can refer me a working cisco PRI configuration example


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spiers Wed, 11/21/2007 - 04:23

Here is all the relevant information from our working configuration, there may be some differences for you based on the information your PSTN provider gives. This configuration if what we use to connect two gateways together via PRI but should work for you as well:

isdn switch-type primary-ni

controller T1 0/0/0

framing esf

linecode b8zs

pri-group timeslots 1-24

interface Serial0/0/0:23

no ip address

encapsulation hdlc

isdn switch-type primary-ni

isdn incoming-voice voice

no cdp enable

voice-port 0/0/0:23

dial-peer voice 555 pots

destination-pattern 555....


port 0/0/0:23

forward-digits all

mohammednw Wed, 11/21/2007 - 04:38


you have to decide what protocol you need to use...prefereably use MGCP....

based on what u decide the gateway configuration will differ...

use the below mentioned configuration for configuring the PRI

controller E1 1/0

framing NO-CRC4

pri-group timeslots 1-31



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