Asterisk as a replacement for Centrex?

I work at a University and we are currently looking into the business case to migrate away from our Telco provided Centrex solution and towards a VOIP solution.

I’m wondering how Asterisk fits into this business model. A key point here is we do not own any VOIP phones, ours are all standard centrex phones.

I realize this is a very newbie question, but thought I"d put it out there.

Thanks for any info.

you can do this easly. you can connect your old centerx ohone with Asterisk Pbx seever with the help of Media Gateway Like Audio code MP 104,108,124 depends on your users.
This Media gateway connect your Analog phone to Asterisk so you can make internal VOiP calls also Out Voip calls.
Aslo you can use ATA for the same but its limitations in number of users.
REgarding SIP peering to connect out side world to make or recive calls with out side world you need to configure all the stuff at Asterisk sip.conf

here i will try to help you you can check with other way also.
If your lokking for VOIp - sip service provide contact here Novanet
Direct- 1800NOVANET


When you say your phones are “standard centrex”, do you mean plain old analog ones, or DMS (e.g. Nortel M5xxx series) phones?

Either way you could use the Citel TVA This unit will take up to 24 analog or DMS phones and convert their signalling to SIP, allowing them to interwork with Asterisk.

Also keep in mind that you can get very good quality IP phones for about $130 and Media Gateways tend to be pretty expensive so it may be cheaper to get new phones.

Thanks for the replies. I’m just trying to get a handle on how much cheaper it would be to go with an open-source vs commercial product. We’d have to buy the phones from the commercial vendor as well, so I guess that part of the cost is somewhat even.

Our big issue would definitely be support and costs.