Global business VoIP services market is expected to double in the next five years and reach $20bn by 2015, according to a report by market research firm ABI Research.

The business VoIP services market is projected to record 13% CAGR in revenues and 19.6% CAGR in terms of lines between 2010 and 2015.

The business VoIP services market includes VoIP integrated access, SIP trunking, hosted IP-PBX/IP Centrex and managed IP-PBX services.

The research firm said that the growth in global business VoIP services market is due to the replacement of legacy phone systems with hosted VoIP technologies by companies.

In addition, with hosted IP PBX services being deployed on scalable cloud architectures, had increased the number of large enterprises replacing legacy phone systems with hosted VoIP services.

ABI Research senior analyst Subha Rama said that among VoIP access technologies, SIP trunking, with its promise of trunk consolidation, centralised management and administration, and application federation across enterprises, has seen considerable growth in terms of installed base and revenues in the last 12 to 18 months.

"Overall, the growth momentum seen in 2009 was sustained in the first half of 2010 as companies continued to shy away from capital investments, opting, instead, for the OPEX model of hosted VoIP services," Rama said.