"The core network used for mobile phones supporting International Mobile Telecommunications (IMT)-2000 standards will eventually converge on Internet Protocol (IP) in 2004 or 2005, said Kazuhiko Masuda, assistant manager of DDI Corp.'s mobile communications' engineering division.
"He presented a picture of next-generation mobile communication systems at the NET&COM21 exhibition in Makuhari, Chiba prefecture. The event ended on Feb. 4.
"In several years' time, voice-over-IP (VoIP) technology will be inevitable in mobile phone networks, he noted.
"The topics of Masuda's lecture -- with a theme of characteristics of high-speed wireless data communication -- ranged widely from expected improvements on existing cdmaOne and personal handyphone system (PHS) phones to the scope of IMT-2000.
"IMT-2000 is a next-generation mobile communication system that features high-speed data communications services up to 2Mbps. In Japan, NTT Mobile Communications Network Inc. (NTT DoCoMo) and Japan Telecom Co., Ltd. will start IMT-2000 services in 2001. DDI plans to follow suit in 2002.
"Masuda also addressed issues for making IMT-2000 services viable. First, it is necessary to make all networks IP-based to use VoIP. Second, the quality of services needs to be assured. Last, it is necessary to develop applications for high-speed communications.
"In the early stages, IMT-2000 compliant mobile communications services from NTT DoCoMo, Japan Telecom and DDI all will be built on the switching network used in today's mobile phone network. Masuda pointed out there are opinions growing among these companies that the core network will converge with an IP-based network eventually, as will outside parts such as wireless access.
"He said that the core network will be built on IP some time starting in 2004 to 2005, and added that some kind of a system to assure quality of services is essential.