>Neil, what hardware would you use to connect to an old Commander system?
>Peter. There are a few ways to adapt a Commander (or just about any PABX). If you have access to spare CO ports on the PABX (ports to connect pstn lines to) and wanted to be able to make or recieve 2 simultaneous VoIP calls, you could just use something like a Linksys PAP2. Probably a hundred dollars or less now with 2 fsx ports. The Commander wont know that the PAP2 isn't a phone exchange. You could do this with no need for Asterisk (though there are reasnons why you might still want Asterisk and you could place calls from the PAP2 through Asterisk). If you use 1 PAP2 on its own, it has a codec limitation when 2 calls are running. It will only make one g729 call. None of the other codecs sound much good except for the higher bandwidth ulaw/alaw. You need to make sure that you have enough bandwith for 2 calls when 1 of them will be at a higher bit rate. A 512/128 ADSL account would struggle with this. Have the Commander programed so that the 2 lines connected to the PAP2 are the first 2 outgoing. Eg dial zero for external and have the 2 VoIP adapted lines used first. You could also use a TDM400P with 2 fxs modules in an Asterisk box to do the same job. About $300 and more complex to configure. I'd probably stick with a PAP2 with the above scenario. For adapting a larger number of lines, probably something like an Octell VoIP gateway. eg there is one with 8 fxs ports for about $800 that you could use on its own or with Asterisk. At the moment I'm looking at using Asterisk as a middleman device for a practice. This would give them VoIP calls from any existing phone and give them access to call queuing on incoming pstn calls. They have 5 PSTN lines. I'll put Asterisk in between the 5 CO ports on the PABX and the 5 exchange lines. This might be with 3 TDM400P cards (up to 4 modules each). Cards populated with 5 fxo (to connect the exchange lines to) and 5 fxs (to connect the PABX to) ports. Reception can use a pin number to specify how many people are available to handle queued calls. I've never used 3 TDM400P cards in 1 box before though. They have a reputation for being crap if they are sharing an IRQ, but even if you avoid that they apparently make lots of IRQ requests causing problems with some motherboards when you use multiple cards. Because of this I'm considering using 2x Octtel gateways. 1 with 8 fxo ports and another with 8 fxs ports. This will give them some room for expansion if they need more PSTN lines for incoming calls. First step will be to get a cabling contractor in to put in a small cabinet to put their network switch in plus a patch panel for the phone lines. The lines can be patched back to the PABX initially & it will make it a snap to patch the Asterisk box or Octtel gateways in between the exchange lines and the PABX. Of course the solution will be different if you have ISDN connected to your PABX. Neil ----- Original Message ----- From: Peter Machell <[EMAIL PROTECTED]> To: [EMAIL PROTECTED], General Practice Computing Group Talk <[email protected]> Sent: Sat 21 Jan 2006 09:52:05 EST Subject: Re: [GPCG_TALK] VoIP providers / Codecs Neil D. McAliece wrote: > It was a DIY Asterisk setup. > > A couple of Dell P4 2.4 ghz machines from a couple of years ago. Unecessary > onboard stuff (audio, usb etc) was disabled. > > They have a basic install of Debian Sarge and I think the second release > candidate for Asterisk 1.2. I should update them sometime soon. > > It makes telephony so flexible. > > Neil _______________________________________________ Gpcg_talk mailing list [email protected] http://ozdocit.org/cgi-bin/mailman/listinfo/gpcg_talk
