Deloitte Touche Tohmatsu (DTT) is deploying an IP telephony system, a move which demonstrates the technology is moving beyond "bleeding edge" and into mainstream corporate acceptance, its CIO claims.

"We did a study of the whole voice-tech [area] about 18 months ago, to develop a strategy moving forward, and at that time thought that IP telephony was still in the early adopter phase, and that, not being a company that necessarily wanted to be in that space we'd wait till it was more mainstream," Tim Fleming, CIO at DTT told ZDNet Australia  .

"I think realising now that it is sufficiently mainstream and seems to be sufficiently robust," said Fleming, adding that because DTT was a firm of consultants it was vital to ensure the phone and e-mail system worked.

DTT are deploying Nortel i2002 IP Phones and i2050 Software Phones - which plug into computers to transform them into virtual phones - following a three month trial of the technology with a dozen users in the IT department and around 20 users outside the department.

"The mobile space was of particular interest to us," said Fleming. "Where you make a VPN connection back to the office which hooks you into your extension number and you can just sit there and make phone calls as though you were sitting at your desk."

"Our Asia Pacific regional IT director uses this extensively and when he rings me I've always got to check where he is because he could be downstairs, or he could be in a hotel in Beijing, and I can't tell the difference," said Fleming, adding the same name and extension number is displayed irrespective of where the call is being made from.

Three quarters of DTTs workforce is mobile, according to Fleming, and the company also makes extensive use of hot-desking - where people don't have a fixed desk but plug their laptops into a free terminal. Using a traditional digital set-up every time someone moves the PABX has to be repatched for them to move their extension number with them.

"In an IP scenario you just pick up your phone and move it with your computer, and when you sit down your extension is transferred," said Fleming.

The trial revealed the main issue with introducing the new technology was training. "[There were] a few little teething issues, you have to make sure you cover off training well, of course, it's something you can't overstate, the importance of the users being well trained," said Fleming. "Particularly if they are using the mobile solution - it gets tough if they haven't been sufficiently trained and they're wanting to make a call from somewhere in Asia on a Sunday afternoon, and they can't do it."

The other issue that has to be dealt with is traffic management. "If you've got multiple sites and you really want to be running your calls across your data network, then you've got to be able to have a data network that's working as much as the public telephone network is working," said Fleming.

"You have to really ensure you have a high availability network, one that delivers quality of service so that the voice calls can be delivered with the highest priority, so that the quality of the conversation is still there."

DTT spent 18 months planning to ensure that its local area networks and wide area network were sufficiently robust to handle the technology. According to Fleming, the trick is not necessarily have massive amounts of bandwidth, but of labelling individual packets so that if there is any bandwidth conflict the voice gets through before the e-mail does.

This requires that the switches the phones plug into can identify the type of each packet and prioritise it accordingly. DTT is deploying a Nortel Networks Succession Communication Server, which also supports a variety of digital, analogue and IP phones. This is important, according to Fleming, because IP handsets cost around twice as much as standard digital handsets.

"If you were buying a thousand phones that's a significant expense, and that's why possibly you may want to ease yourself into it," said Fleming.

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