I’m looking setting up an Asterisk box at work. We will have approximately 16 extensions (I think the Sipura SPA 841 looks like what I need) and require 4 PSTN lines in. We are in Australia and currently have 4 PSTN lines running into our accient PABX system.
Can any one give me some pointers? Especially with the PSTN card options. I’m thinking of plugging the Asterisk box into the corporate network, and the IP phones plugged too in each room. Is this the right chain of thought?
Any help or guidance that can be given would be greatly appreciated.
The digium TDM04B would be a good choice for you to connect your analog lines to the Asterisk server. It has 4 analog line cards. Just what you need.
The 841 is a good all around phone, and the power supply is very adaptable, so Aussie power jacks should not be an issue.
Things to consider:
You’ll need a power jack for each 841 as well as an ethernet jack everywhere you plan to install a phone. Many phone installations have wiring for a phone, but there’s no power plug nearby. Sadly, the 841 can’t do power over ethernet.
Do you have a fax machine (or any modems) going through your PBX? If so, you’ll want an FXS card to connect it through the Asterisk server or just get a 5th phone line, and leave it off the Asterisk box.
If you’re looking for really good speakerphones, the 841 isn’t it. It’s ok, but not great. They work fairly well in small offices for a single user. Don’t expect to make it a conference room phone. They also have the WORST handset cord. Buy 16 of those as well. They could use some body weight too. They’re small, and light, and I’ve had trouble pulling them around (and off) my desk with the handset cord, so if there’s an option to wall mount them where you plan to use them, I’d shoot for that. Ohewise, I’d attach them to one of these with screws:
You’ll need UPS’s for at least 1 or 2 phones and the Asterisk server, or you’ll want to connect an analog phone to your incoming phone lines (turn the ringer off) for loss of power emergencies. If the power goes out, you’ll still want a way to make a call.
Be sure your network is good enough to handle the traffic. Ideally full duplex 100 ports on your switch and on the Asterisk server. That’ll minimize audio quality issues.
Thanks heaps for your information. It is slowly sinking in.
Another curve ball, what interface card would I be looking at if I wanted to use ISDN lines instead of the PSTN? Here in Australia a normal ISDN service consists of two B channels and a D channel. So we would be looking at two ISDN lines (4 B channels).