... change.In the past, an enterprise purchased their phone system from one vendor. The entire system was proprietary, and the phones and the system came from the same vendor. If you liked the features ... Alcatel, Avaya, Mitel, Nortel, and Siemens. Since then, these and many other vendors have developed their own proprietary VoIP systems inresponse to the growing demand for VoIP systems.Traditional ... America and South Korea, and is dedicated to the prolifera-tion of a third-generation wireless global standard. More specifically, this organization focuses on the develop-ment of standards for the...