The ability to use it with SIP phone like Vtel, is one of its main advantages because we can have many users at once in our office without having problems in voice quality or latency. The software does not support other protocols than sip as far I know, but if you need that functionality just go ahead! It's really fast when using high speed internet connections (at least 100mbit) which makes very important work easier. We are solving several issues related to audio communication within our organization by providing solutions through this product.