Frost & Sullivan estimates that the cost of an open source telephony 'line' can be up to 40 per cent less than an averagely priced proprietary IP PBX/Communication Manager.
The analyst firm's European Open Source Telephony Market report notes that total cost of ownership comparison indicates a similar picture, with the cost benefits far greater in a call centre environment and in settings where the proportion of 'professional services fee' is higher.
Frost & Sullivan said that the market shipped more than 74,000 lines in 2007 and estimates this to reach 1.95 million in 2013.
"Our research finds that many of the open source telephony vendors have been enjoying a very high growth rate," said Frost & Sullivan research analyst Dorota Oviedo.
"Several notable open source telephony vendors are investing in the European market, and 2008 will be dominated by channel activities, especially channel recruitment and training.
"Established participants will be investing to expand their footprint mainly through distribution."
But Oviedo went on to warn that "mindshare" and user acceptance of open source telephony is "relatively low" at present.
As a result open source telephony vendors face a "huge challenge" in competing against participants that use proprietary technologies.
These vendors benefit from their well-established legacy market position, brand image, strong distribution network and strong relationship with the customer base.
"The biggest challenge that the open source market has been facing and gradually overcoming is the issue of negative market perceptions," added Oviedo.
"Open source projects are relatively young and struggle with market concerns and perceptions of lack of support, scalability, functionality or reliability."
Frost & Sullivan said that open source telephony vendors should invest in building awareness through site visits and publishing success stories.
Research suggests that, once prospects overcome the initial reluctance and run a test system, the success rate for open source telephony deployment is relatively high.