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Summary Taking into account the developments of ICT in recent years, a lot of countries are dealing with the preparation of statistics on ICT. In Japan, the Basic Law on Formation of an Advanced Information and Telecommunications Network Society (Basic Law on IT) was enforced on January 6, 2001, in which the Government is obliged to prepare official statistics related to ICT. In Japan, at least 41 kinds of official statistical surveys, including questions related to ICT, have been conducted in the past five years. Their main purpose, survey items and survey methods are various and different from each other. To grasp the new development in IT as a whole, “IT Indicators in Japan”, which is a new compendium on ICT, was compiled in 2001. Also, “Information and Communications in Japan”, which is a white paper published in 2001, presented basic data on the extent to which IT has permeated the economic activity and people's lives. In addition, the 11th revision of the Japan Standard Industrial Classification (JSIC) was published by the Statistical Standards Department, Statistics Bureau, Ministry of Public Management, Home Affairs, Posts and Telecommunications (MPHPT) in March 2002 in response to the change of economy and society including the development of ICT. The Working Group on Indicators for the Information Society of OECD has been working for several years in order to prepare internationally comparable and statistically measurable ICT indicators and related ICT statistics. In this paper, an overview of the present situation of Japanese official statistics related to ICT is given with some analysis. In addition, some problems are raised which should be considered from the viewpoint of the necessity and measurability and so on for the appropriate preparation of ICT indicators and e‐commerce‐related statistics. “IT; Information Technology” and “ICT; Information and Communications Technology” are often used without any distinction. “ICT” is used in this paper except where “IT” is used as a proper noun, as it is considered almost the same as “IT”. The views expressed herein are those of the author, and are not necessarily those of the Statistical Standards Department or any other Japanese government authorities.

In HTTP adaptive bitrate (ABR) streaming, the ABR algorithm is an important factor determining the quality of experience. Traditional ABR methods control the bitrate of individual clients autonomously so that the quality variation occurs even when the bandwidth of a delivery network is managed. Here, we propose a server-side ABR method achieving quality fairness among clients and suppressing a quality variation over time in networks where external applications dynamically control the quality of service. The method controls both the bitrate and delivery bandwidth based on a perceptual quality score. We evaluated the basic performance of the proposed method on an experimental network whose bandwidth could be controlled by the API. We confirmed that the proposed method could maintain the target quality within the upper-limit bandwidth and suppress the quality variation among clients and over time.

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The amount of high-definition content has been increasing significantly lately, and there is also growing demand for video delivery services. This article introduces technology intended to address these issues. It achieves this by delivering high-definition and high-presence video content with high quality in an economical manner by optimizing the server deployment and communication network of content delivery providers and communication providers and by implementing new delivery control techniques.