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PBX interoperatibility with router

Dear ALl

I have a confusion regarding the PBX integrations with Router.

Now if i am integrating my 2801 router with any PBX trunk ports (by trunk ports i mean the ports used to connect with PSTN with normal RJ-11 connector) , do i really have to worry about the compatibility between router and PBX.

The reason is that if the PBX can terminate the lines from the PSTN (RJ-11) than it should work with my router too .It is with e1 when we should worry about compatibility .Am i correct.

So what ports do i need on the router side?FXS.i thnok so as when we connect pstn with PBX than PSTN provides the tone ,so now my router should provide the tone to PBX trunks.

My scenario is that eight lines from PSTN are terminated in the norstar PBX and as i am proposing the IPT system the lines will now be terminated into the router and than the router should forward the call to the PBX if it is for any analog phone .

So my real question is do i really need to worry about the PBX interoperability when i am dealing with analog trunks.


Hall of Fame Super Gold

Re: PBX interoperatibility with router


the short answer is if even FXO is barely acceptable to connect to the PSTN (you should really get at least ISDN BRI), FXS/FXO connnection to the PBX will be certainly too limiting. Many problems of double dialing, potential stuck ports, no passing of information, etc. etc. The very miniumum is E&M to the PBX but real good would be again, ISDN BRI or PRI.

If the PBX is missing the necessary cards and is not worth to buy them, the you should at some point look at replacing the PBX completely.

The answer to real question is yes, you should really worry about analog trunks if you want the integration be of a professional level.

Hope this helps, please rate post if it does!