Packet writing

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Optical disc authoring

Optical disc Optical disc image Recorder hardware Authoring software Recording technologies Recording modes Packet writing
Optical media types
Laserdisc Compact Disc/CD-ROM: CD-R, CD-RW DVD: DVD-R, DVD-R DL, DVD+R, DVD+R DL, DVD-RW, DVD+RW, DVD+RW DL, DVD-RAM Blu-ray Disc: BD-R, BD-RE HD DVD: HD DVD-R
Standards
Rainbow Books File systems ISO 9660 Joliet Rock Ridge Amiga extensions to Rock Ridge El Torito Apple ISO9660 Extensions Universal Disk Format Mount Rainier

Packet writing is an optical disc recording technology used to allow writeable CD and DVD media to be used in a similar manner to a floppy disk. Packet writing allows the user to access the contents of a CD-R or CD-RW disc directly through a mounted filesystem (Unix, Linux, Mac OS X) or drive letter (Windows). Without packet writing software, one would have to use regular CD mastering recording software to burn a whole disc.

Packet writing can be used both with once-writeable media such as CD-R, DVD+R and DVD-R, and also with rewriteable media such as CD-RW, DVD+RW and DVD-RW. Once-writeable media cannot however recover space once used; A deleted file does not free space on the disk, and a modified or overwritten file occupies additional space even if the file size has not increased. When the free space on a once-writeable disk is exhausted, no further update to the disk is possible. Rewriteable (RW) media can have all the files deleted on a formatted disc, or information can be overwritten. The downside is CD-RW will fade to the point it isn't readable as the re-crystalized alloy de-crystalizes. Formatted CD-RWs seem to fade out faster than unformatted CD-RWs. People who assume RW media can be updated and reformatted many times just like a floppy disk eventually discover that their data has disappeared. And there are only so many times it can be COMPLETELY erased and reused - it varies from disc to disc, and can vary with age and use.

Several competing and incompatible packet writing disk formats have been developed, notably those of Roxio DirectCD, Nero AG InCD, and Sonic Solutions Drive Letter Access. Proposed standards include UDF 1.5 and Mount Rainier.