KDDI
KDDI Corporation TYO: 9433 is a Japanese telecommunication operator formed in October 2000 through the merger of DDI, KDD, and IDO Corp. KDDI provides mobile cellular services using both the au and the Tu-Ka brands, ISP network and solution services in the DION brand, and long-distance and international voice and data communications services, optical fiber (Triple play services und the brand name Hikari Plus) and ADSL broadband services and IP telephony over copper under the brand Metal Plus.
On April 1st, 2002, KDDI launched 3G networks using cdma2000 1X technology. On November 28, 2003, au/KDDI launched cdma2000 1xEV-DO service in the CDMA 1X WIN brand, and revolutionized Japan's mobile telecommunication industry by introducing fixed rate data subscription plans at a data rate of 2.4 Mbit/s.
au/KDDI has been very successful with its EZ wireless data services, EZweb, EZweb@mail, EZappli, EZchakuuta, ezmovie, and eznavigation (GPS), using the advanced WAP technology. It supports both J2ME and BREW application environments.
au/KDDI is particular popular among students with special discount plans. All enabled by its efficient CDMA2000 network.
In December 2004 au/KDDI introduced the music download service Chaku Uta Full, for download of full length songs to mobile phones. Within six months from introduction, on June 15, 2005, customers had downloaded 10 million full length Chaku Uta Full songs.
As of end of June 2005, au/KDDI has 20,122,700 customers, among which 18,723,200 (93 %) are 3G CDMA2000 subscribers. It is Japan's second-largest cellular operator with an increasing 20.0% market share.
TU-KA, a subsidiary company of KDDI, is a 2G PDC cellular operator who did not apply a 3G license.