To connect PSTN with Router do we need FXO or FXS

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Jan 18th, 2010
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My client need to connect a PSTN number  [ 22445566] with the voice gateway 38XX; 38XX is used as MGCP gatewaywith CUCM 7.1; do I need to use FXO or FXS card to connect voice gateway for teleco connection, when there is an incoming call from this PSTN number 22445566, we should made to ring a PSTN number.

Please light me it is possible to configure this.

Correct Answer by Doan Khanh Tan Thanh about 7 years 4 months ago

"connection plar" command should be use on this case.

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Overall Rating: 5 (1 ratings)
Jaime Valencia Mon, 01/18/2010 - 04:51
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Read this and you'll understand what the difference is

Understanding Foreign Exchange Office (FXO) Voice Interface Cards

Understanding Foreign Exchange Station (FXS) Voice Interface Cards



If this helps, please rate

BALAMURUGAN SINGARAM Mon, 01/18/2010 - 23:37
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Thanks for the reply, so from the URL Link, myself understand that to connect teleco and voice gateway we need FXO card only, please correct me if I am wrong ?

One more question, I am integrating FXO port with MGCP gateway, how to ring an IP Phone with FXO integration.

I have one PSTN line 22445566, want to integrate this line with FXO, then the incoming call should be get land on IP Phone.



BALAMURUGAN SINGARAM Tue, 01/19/2010 - 01:51
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Could you please help me with more configuration will help me lot.

It is poosible to connect FXO to a teleco line and we can call an IP Phone in the CUCM cluster, please light me with more information on this.

cisco.amit Tue, 01/19/2010 - 03:19
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Please check form cisco site the cme configurtion for PSTN line on FXo card.

the configuration is not too much, it is just like it:

insert the card

check in the router by show version or show diag

then u see port 0/0/0 or 0/0/1.....where u pu the card in the slot of router

then use connection plar command

create a dial peer for incominga dn for outgoing

adn assing this port under outgoing dialpeer.

that is the final point to do it completeand get call.

for trace chekc by debug voip ccapi inout and chekc if stuck naywhere.

BALAMURUGAN SINGARAM Tue, 01/19/2010 - 03:51
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My voice setup is with CUCM 7.1 and MGCP voice gateway, just connecting FXO card in voice gateway will help me to call internal number of CUCM also.

Please give me URL for FXO configuration.


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