Standardization for High-interoperability between Optical Disk Systems

June 1999

1. Purpose

This project (F-project) studies and develops technologies for acceleration of information interchange via optical disks to propose some international standards for interoperability of optical disk file systems. A conformance testing environment for UDF (Universal Disk Format, an OSTA instance of the volume and file structure specified by ISO/IEC 13346) is actually developed. Some extensions to the UDF are discussed to be standardized for more sophisticated interoperability of optical disk systems including the support facilities for security, access control, etc.

The activities of F-project are carried out by a committee of OITDA on the foundation of research and development of JSA (Japanese Standards Association), which is controlled by NEDO's plan of "International Standards Creation for Promoting Industry" originated in fiscal 1998 and to be completed in 2000.

2. Background

A number of products of optical disk systems are available on market. We can obtain a number of optical disk media, e.g.., CD, MO, PD and DVD, and several operating systems. However, the information interchange between the systems via those optical disks are restricted to some extent from the application's point of view.

ISO/IEC JTC1 standardized a generic media-independent volume/file structure and published it as ISO/IEC 13346. OSTA (Optical Storage Technology Association) defines some implementation specification of the ISO/IEC 13346 to be the UDF. The UDF is updated according to user requirements for some media and has already been actually implemented in some products by vendors.

For more increase of optical disk market and business, it could be indispensable to recognize application user requirements for information interchange by optical disks and develop file systems including support facilities for satisfying all the requirements. Those file systems should be interoperable with conforming to the new international standards for the support facilities as well as conforming to existing ISO/IEC 13346 and UDF.

3. Activities

The actual works of the F-Project in 1998 were taken by the Committee of Optical Disk High-interoperability (chaired by Prof. K. Itao, Univ. of Tokyo) and its working groups.

3.1 UDF conformance testing

The UDF has been implemented by several vendors. They interpreted some of the UDF specifications differently from each other. Therefore they requires appropriate conformance testing tools for UDF file systems. OSTA proposed a specification of UDF compliancy test disk.

The F-project developed and released a program to generate images of the UDF compliancy disk (ver. 0.04). It was reported in the OSTA meeting. Using the program the users can generate their test images defined by OSTA.

3.2 UAF (Universal Accessible File) System

Today's applications of optical disks require such additional features as security, access control, partial copy, etc. preserving open interchange of data. Those features are supported by the facilities allocated at the superior of existing UDF functionalities. The UAF system includes all the support facilities as well as UDF compatibility. The support facilities should be standardized for realizing UAF interoperability.

In the 1998 activities of the F-project, we clarified the user requirements for UAF systems in our discussions, for example, in the workshop held in Dec. 1998. The user requirements are to be reflected in the specifications of standards which will be developed in our 1999 activities with precise feasibility checking. For the feasibility checking we actually developed a UAF estimation environment.

4. Future Plans

In our activities of 1999 and the later we are planning to develop the following systems and standards: