According to ResearchAndMarkets, the global service provider voice over Internet protocol (VoIP) gateway market at $165.3 million in 2003 is expected to reach 985.7 million dollars in the year 2009. The market is anticipated to grow at a steady positive rate over the years. The growth is brought by replacement of digital proprietary voice switching systems with systems that do manage to put voice over the Internet reliably and clearly.

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Voice Over Internet Protocol (VoIP) Market Opportunities, Strategies, and Forecasts, 2004 to 2009 - Research and Markets - Market Research Reports