Hi guys,
I would like to revive this topic -- connecting 3CX with Panasonic IP PBX (NCP, TDE). In my case I have in place Panasonic IP PBX as main PBX for the organization. I'm installing a 3CX for department PBX, using public trunks from Panasonic (ISDN) plus new pure VoIP into the 3CX.
One way to connect Panasonic IP PBX and 3CX is to establish 3CX bridge between them -- 3CX being master and Panasonic being slave (via SIP trunks). In this case you may have as many channels (simultaneous calls) you want, of course limited by licenses (number of IP trunks in Panasonic and number of Simultaneous calls in 3CX). You can call extensions in each PBX (subject to dial plan in Panasonic and Outbound rules in 3CX). You can forward external incoming calls (arriving in Panasonic) via DDI table and private network (and COS settings) but you can NOT make outgoing call from 3CX extension via Panasonic trunk lines – Panasonic is not allowing trunk-to-trunk calls (private to public network or public to public) - this is only possible from another Panasonic PBX via H.323 interconnect lines. It is possible to use 3CX trunks for outgoing and incoming calls from/to Panasonic extensions via the bridge, even sending the originator's caller ID from Panasonic (PBX CLIP) to SIP trunk in 3CX.
The other drawback of using 3CX bridge is that the Panasonic users see as extension name the number of the 3CX bridge (i.e. 10000 or similar). It is not possible to alter this like in outgoing parameters settings for VoIP providers in 3CX. It is possible to overcome this by creating a generic SIP trunk (without registration) in 3CX to Panasonic to port 35060 and use it for outgoing calls only. If you want to use it for incoming calls you may still use the bridge (with registration) or connect a SIP trunk to 3CX (without registration) but with allowed direct SIP calls in advanced settings of 3CX.
Coming back to the point of making outgoing calls from 3CX extensions via Panasonic trunks (not possible vai the bridge), I tried the following - registered 3CX SIP trunks to Panasonic SIP extensions (needs SIP extension licenses in Panasonic). In this way you overcome the limitations in 3cx caller's presentation to other Panasonic extensions (may need many licenses in Panasonic) and can make outgoing calls via Panasonic trunks with correct Caller ID (PBX CLIP).
The serious problem I met with this approach (SIP trunk to SIP extension) is that from time to time (completely random) the 3CX trunk is not registering as Panasonic SIP extension. The error code is 403: forbidden (from 3CX log). This is not affected by 'registration attempt interval' in provider's settings in 3CX neither by Panasonic general SIP extension settings parameters (time to re-register). If this happens, the 3CX is attempting to re-register in 10 minutes (meaning no service for these 10 minutes), also not possibe to alter in 3CX.
The strange thing is that the 3CX softphone is not experiencing this problem, only the 3CX phone system. I'm using the latest version 10 SP1 commercial edition. Does anybody have idea how to handle the case?
There are known problems with registering certain SIP phones to Panasonic, but this is different -- you can have successful registration for several hours and suddenly you lose it for 1 or 2 periods of 10 minutes.