An office that I consult for has a current Nortel Norstar system that they want to continue using as their primary phone system for the time being while they get their feet wet with SIP Trunking. What we're looking to do is connect a 3CX box to a the Nortel system via a T1 connection between the two... Should this work? We currently have the a T1 PRI connected to the Nortel via a local phone provider. I'm thinking about using a Sangoma A101E card and then just running a 10 foot cable from the A101E to the Nortel system. Will I be able to set up 3CX to do this. Also, is Echo Cancellation necessary for the T1 card that I'll be using? I was figuring that it wouldn't be since it is just connecting the 3CX box to the Nortel system but please let me know if my understanding is incorrect. I haven't used 3CX yet for anything other than taking a SIP trunk in and passing it out to SIP phones. Thank you.