The Rock Ridge Interchange Protocol (RRIP, IEEE P1282) is an extension to the ISO 9660 volume format.

It's commonly used on CD-ROM and DVD media, which adds POSIX file system semantics. The availability of these extension properties allows for better integration with Unix and Unix-like operating systems.

(RRIP was developed by Andrew Young of Young Minds, Inc. in the early 1990s. The standard takes its name from the fictional town Rock Ridge in Mel Brooks' film Blazing Saddles.)

The RRIP extensions are, briefly:

  • Longer file names (up to 255 bytes) and fewer restrictions on allowed characters (support for lowercase, etc.);
  • UNIX-style file modes, user ids and group ids, and file timestamps;
  • Support for Symbolic links and device files;
  • Deeper directory hierarchy (more than 8 levels);
  • Efficient storage of sparse files.