Voice over Internet protocol (VoIP) can be implemented in two ways: calls can originate from the traditional TDM circuit switched technology, or originate from an Internet protocol router. IP to TDM and TDM to IP VoIP are very different. These fundamental differences in technology referred to as the same term (VoIP) have served to confuse the market, with distinctly different products being positioned as VoIP solutions.The research firm expects that the VoIP market will grow to 985.7 million dollars in the year 2009.
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