CAMPBELL, USA: Global VoIP service market weathered the economic turmoil of the last couple of years, and, with increasing customer adoption, reached $49.8 billion in 2010 (compared to $34.8 billion in 2008), finds market research firm Infonetics Research in its latest report.

Infonetics Research forecasts the combined business and residential/SOHO VoIP services market to grow to $74.5 billion in 2015.

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"While the residential services segment remains the largest of the market at 69 per cent of total revenue, business VoIP services are growing at faster rates; a notable example: SIP trunking had a breakout year with 143 per cent revenue growth in 2010," notes Diane Myers, directing analyst for VoIP and IMS, Infonetics Research.

It also adds that managed IP PBX business VoIP service revenue is expected to more than double from 2010 to 2015. The fastest growing segments of the VoIP services market are SIP trunking and hosted UC telephony.

NTT of Japan retains its leadership as the world's largest residential VoIP service provider, followed by Comcast and France Télécom.

The number of residential VoIP subscribers increased 19 percent in 2010 to 157 million worldwide.

Based on healthy demand for cloud-based services, the number of seats for IP Centrex and hosted UC services grew 20 percent in 2010.