Yeastar MyPBX Enterprise M2 is a hybrid IP-PBX, which is designed for mid-sized companies and divisions of large organizations. Besides working with VoIP-SIP and IAX, the device works effectively with connection to analog phone lines like traditional telephony.
Lingo is one of the most affordable U.S. Internet phone services. Lingo offers unlimited local and long distance calls anywhere in the U.S., to Canada, and to Western Europe, plus over 25 calling features