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problem connecting isdn bri voice interface to pstn

i'm trying to configure my ISDN BRI NT/TE voice interface card (VIC-2BRI-NT/TE) on router 3825 to link to my PSTN provider. This must allow my Cisco IP phones to pass call to the PSTN through my call manager 4.1.

I suscribe to two isdn line. The provider told me that the SWITCH TYPE is VN6 (COTE d'IVOIRE or Ivory Coast).

For my bri configuration, see file "interfaces configuration..."

My problem is that when i pass call from my Ip telephony network, the first call goes well. But after this first call, when i type the command isdn status, i can see that the layer 1 of my isdn interfaces are DEACTIVATED, and after a few minutes, it turn back to ACTIVE. During these minuite, i can't pass any call through my isdn interface.

for outputs of show isdn status command, and isdn debug q931 commands

see file "show isdn status and debug..."

Notice: when the status of the isdn layer is in the deactvated status, i can receive call from the pstn, but i can't passe call to pstn (the state changes to ACTIVE when incomming call from pstn arrive, but still stay DEACTIVATED when outgoing call is initiated)

Please help me


Re: problem connecting isdn bri voice interface to pstn


can you please set the "isdn static-tei 0" interface command?



New Member

Re: problem connecting isdn bri voice interface to pstn

I've entered the "isdn transition-delay 1" interface command and things seem to work well.According to the IOS help on my router,this command clears the ISDN D-CHANNEL after a delay of 1 second.

But i would like to get more information on this command, and also on the isdn layer 2 and 3 timers, and even possible on all the "isdn" interface command option.


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