なぜワイヤレスATMは失敗したのか

摘要

There have been a number of significant successes in the area of mobile multimedia communications along with the remarkable growth of cellular communication markets. Meanwhile, there were also a number of failures in terms of technologies and businesses in this area. This report presents one of these failures—wireless asynchronous transfer mode (ATM) technology, which attracted considerable attention in wireless communication circles in the mid-1990s. Wireless ATM was developed to connect seamlessly to backbone ATM networks and to realize the future mobile multimedia services with a guarantee of quality of services (QoS). However, the development was declined within several years, without building up a market. Its background, history, and causes of the failure are described. The primary causes can be summarized as follows: (1) the technological trend of communication networks had changed from ATM-based to Internet protocol (IP)-based; (2) the technology was so complicated as not to realize inexpensive and low-power devices for end-users; and (3) those involved in the development overvalued the technology's advantages (high efficiency of the networks and capability of QoS guarantee) over IP.%モバイルマルチメディア通信分野では，セルラ移動通信の成長に伴い，数多くの成功例がある．一方，市場に出たもののビジネスとして成功していないものや，市場に登場することができなかった失敗例も存在する．ワイヤレスATM（Asymchronous Transfer Modc）技術は1990年代に活発に研究が進められ，次世代マルチメディアの基幹技術として全世界で注目を浴びていた．しかし，研究が開始されてわずか数年で衰退しワイヤレスATMは姿を消すこととなった．本報告では，ATMの研究が開始されたバックグラウンドから競合技術であったワイヤレスEthemetに敗れ技術が衰退するまでの経緯を分析する．失敗の要因としては，（1）情報通信の趨勢がIPに変化したこと；（2）普及・進歩を阻んだ技術的要因；（3）ATM技術の特徴を過信していたことが挙げられる．