Hi Guys. I used to use 3CX a while ago whilst carrying out training but its been a while now. I have come back as i have a new comms problem. In our current building we have an old Nortel Norstar system, 10 extension with 4 lines coming in. Now we have an additional building with no system in but it does have ADSL. What i was hoping to do was install a 3CX system in the new building with 10 extensions, and install a 3CX system in the old building with another 10 extensions. I would create a trunk line between the two so that to the user, it is seamless. However, first of all, i do not know if it is possible in 3CX to have such a system, and secondly, what hardware would be i be looking at to interface with the ISDN system. We are looking at keeping our original ISDN system in, purely for a backup and also as the incoming gateway for customers that already have our number. I would love to hear any suggestions or anyones experience from interfacing a 3CX PBX with ISDN/Nortel systems. Thanks.