Please contact Media Sciences if your questions are not answered on these pages. Non-conforming discs may be readable in forgiving systems, but will fail in others. ISO 9660 defines basic requirements for data interchange, and also provides for optional extensions to specific operating systems such as Windows, UNIX, and Macintosh environments. Three ISO 9660 levels control file and directory name lengths, directory depths, and file fragmentation permissions. Each of these elements is managed by pre-mastering software that may not comply with the requirements of ISO 9660 and its extensions.
Unpredictable interchange can result.
Data CD disc mounting always begins with the drive reading the Primary Volume Descriptor in sector 16. 9660 Level 1 requirements specify important information, including the location of path tables and the root directory, that is contained in this descriptor. Precise rules must be followed concerning character sets, byte ordering, and 8.3 name lengths. Path tables provide a shortcut through the directory tree in order to reduce otherwise long seek times. Dual path tables provide both big endian and little endian byte ordering.