Having completed its campus-wide wireless network last year, the University of Queensland (UQ) in Brisbane has joined the handful of enterprises deploying the open source Asterisk IP-PBX for staff and student VoIP.

Scott Sinclair from the university's strategic technologies group told Computerworld new technologies are always being investigated and VoIP could reduce call costs, particularly between the smaller campuses which are already linked by fibre.

"We have a commercial ISP as part of the university so providing commercial VoIP with Asterisk would be good," Sinclair said. "We're looking at a number of products but the easy and inexpensive way to get into [VoIP] is with open source."

While making a name for itself among open source and IP telephony circles, Asterisk, which runs on Linux and Unix, has little to show for widespread enterprise adoption. Its flagship end-user sites include Melbourne-based department store chain Adairs, and Copiah-Lincoln Community College in Mississippi.

"So far we have successfully integrated Asterisk with the traditional TDM and are now looking at the presence functionality it provides," Sinclair said.

"We only have a small deployment but it's been successful so far. Being able to advertise the multiple places where you are is a powerful feature." UQ's Asterisk system consists one x86 server running Red Hat Linux.

Sinclair is excited at the possibilities of VoIP for some 5500 staff and 35,000 students when "their e-mail will become their phone number using the SIP protocol".

About 10 people are using Asterisk now, but UQ will soon begin a pilot project with one of its residential colleges to supply VoIP to students' rooms. This will involve some 200 users.

"It's conceivable for each student to have a phone number [and] that could be rolled out now, it's just a case of finding apps that will use it," he said. "Students won't have to pay a toll and since every student gets a local call dial-up account, they could make calls from home. You don't need CD quality for voice."

With the call quality with Asterisk "good", UQ's strategic technologies group manager Dr Rodney McDuff discovered one bug in the software and, with the aid of the Asterisk development team, wrote patches to fix it.

Sinclair is also interested in the application integration possibilities IP telephony brings, like accessing voicemail as an mp3 file through the myUQ student portal.

"We have a pretty big blackboard installation so we're looking at collaboration and meetings," he said. "We certainly want to have people call in over IP telephony. We'll also look at softphones for VoIP over the wireless network."

While Asterisk is open source and free, Sinclair said more testing and design considerations still need to be worked through before it is deployed in production.

"QoS will be an issue, and you have to have UPSes and redundant networks," he said. "When you have 60 to 80 buildings on campus every switchboard will make use of it."

Asterisk's place in UQ's design is to provide features like voicemail, queues, auto attendants, and call access control. Either Cisco or NEC SIP-PSTN gateways will be used because they use hardware for transcoding media streams, and another open source product, SER (SIP Exchange Router), or Cisco Call Manager 5 as the SIP proxy-registrar.

McDuff said SIP and Asterisk scale "quite well horizontally" and he sees no problems scaling UQ's VoIP infrastructure to meet demand.