VoIP (Voice over Internet Protocol) is a far more viable technology that it was two years ago, according to Gartner analyst Geoff Johnson.
Johnson told a Nortel Networks briefing in Auckland last week that there are two classes of VoIP vendors: the new entrants, such as Cisco Systems and 3Com, and traditional PBX vendors like Nortel and Alcatel SA.
The new entrants push VoIP as "just another application on your highly resilient data network", and stress that switching to VoIP avoids the cost and disruption of upgrading proprietary hardware.
By contrast, the traditional PBX vendors emphasise extending the voice network with seamless functionality, thus avoiding the "forklift" upgrade, or complete replacement of PBXs, instead going for phased migration in which PBX hardware continues to be used but a hybrid system is installed.
Nortel Asia-Pacific VoIP solutions portfolio director Chris Luxford says phased migration made sense. "Why throw out technology that's working well today? Most PBXs still have some depreciation left."
Johnson says VoIP is the strategic direction for both PBXs and WANs and IP telephony vendors are catching up with traditional telcos in their offerings.
A reason for some early VoIP failures is that the technology was implemented in situations where networking layer 3 wasn't up to VoIP, he says.
"Ninety per cent of failed VoIP installations are caused by poor implementation and lack of understanding of what's required."
Architectural insurance and making sure you have an adequate service-level agreement with your VoIP vendor are ways to avoid such mistakes, Johnson says.
The ideal place to put in VoIP is where there are fewer than 100 phone lines and it shouldn't be considered unless it will result in a lower cost of ownership of the organization's voice system and the level of features, security and reliability supported by the present PBX can be exceeded.
The "sweet spot" for VoIP implementation is a small single site, perhaps a remote branch of an organization, with limited voice requirement and where moves, additions and changes (MACs) can be managed remotely -- along with fewer toll bills, one of the major cost benefits of VoIP.
Johnson acknowledges there are also expenses involved.
"IP phones cost as much, or more than the existing feature set, server-based hardware is not necessarily cheaper than proprietary hardware and adding IP devices isn't any easier than upgrading legacy hardware."