I'm looking for something to provide outgoing and incoming VOIP calls in an office environment.
Would need to receive 'ordinary' PSTN calls (and call them)
We would be looking for about 20 extensions.
Handsets could be either on PCs or IP based.
Currently we have MS SBS server 2003.
We currently have some 0845 numbers which we can 'point' at places.
Does anyone know of something to go on SBS?
Is Asterisk the way?
Can PNet provide anything?
Well, I'd have to say asterisk is the way - it works a treat and is relatively straightforward to setup, although there are ports of Asterisk to windows I wouldn't recommend them for the home user - let alone a business one! Your best bet would to get a machine running linux, and install and configure asterisk - if all you want to do is have 20 extensions that can make and receive VoIP and PSTN calls then that's really simple. It's also recommended that for outgoing dialing you have a fast business internet connection for asterisk to use and a reliable VoIP provider. I've personally been having a few problems with asterisk and PlusTalk, but you might find it a different experience all together - just make sure that you introduce the system gradually - so you've still got your POTS setup to fall back on to.
It will also depend how many calls you anticipate to handle at once (there are 20 extensions, but will you have people in a call queue etc.?). Softphone/hardware (IP) Phone is just a matter of preference really, obviously using a softphone will save you a bit of money - you'll also need to fork out on a reliable ATA (analog telephone adapter) which would hookup your PSTN line to asterisk.