Evening all,

We have recently been toying with the idea of dumping our ageing(but in perfect working order)NEC TDM phone system, to the point of running a small trial for some home based distance learning tutors.

Dell 2950 server with an 8 port OpenVox card with 6 FXO modules. These modules are then connected to 6 analogue ports on the old PBX, and I have programmed the server to give one line to each of the 5 new people(with a DDI on each one, and them locked to one line, effectively giving them a private trunk) and one to their manager(based in France, that's distance learning for you!) They then use the Jitsi soft phone client and a headset to connect.

Works swimmingly well, the odd hiccup with them not initiating the VPN before the phone software, isolated hanging up detection problems, but on the whole, no echo and happy users.

So now that's working and testing well, I want to start thinking about scaling up to everyone desk in the organization, 4 regional centres all connected with fibre based leased lines, some 80 ish seats, plus the 10 or so people who work from home, who will have soft phones.

The test is on Elastix, which works lovely but is a little on the feature intensive side, I'm surprised Kitchen Sink isn't a menu option!

I have now started building a PBX in a flash server, 1.8 Asterisk with 2.10 FreePBX, brown i believe, as it fits more into the start small and secure, add what you need as you go along category. This is on an old 1u Dell dual xeon, 2GB server, but it will move to the 2950 if I get a go in the distant murky future.

What do people think about all the different distros of PBX? Are they all a bit much of a muchness or do some win more than others?

Should I have one single server and just connect endpoints over the VPN's or have a server at each centre? Plan is mostly SIP desk phones with the odd softphone(I am playing with a 7961G in SIP mode at the moment, and it works very well(ringing voicemail mainly!), and probably 20 sip trunks. We can either have all the sip trunks hanging off a main server(100MB line) at HQ or spread them around the centres on distributed servers. Which is best for good service to my users?

The question of fail over etc and loss of phones if VPN fails will come up, but each centre already has a phone system hosted by the buildings we reside in, so if things go down, they plug their old phone in again and off they go, so resilience and fail over doesn't really come into it at this point.(If the VPN is down, most likely so is the internet, so a local server would be useless as well)

Anyone done this, any pitfalls or gotchas?

Any advice appreciated, and if I can help anyone get started on the path to IP telephony, don't hesitate to ask.