Packet writing
Encyclopedia
Packet writing or IPW (original term: Incremental Packet Writing), is an optical disc recording technology used to allow write-once and rewritable CD and DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....

 media to be used in a similar manner to a floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...

 from within the operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

, i.e., it allows users to create, modify, and delete files and directories on demand without the need to burn
Optical disc authoring
Optical disc authoring, including DVD and Blu-ray Disc authoring , is the process of assembling source material—video, audio or other data—into the proper logical volume format to then be recorded onto an optical disc .-Process:To burn an optical disc, one usually first creates an...

a whole disc. Packet writing technology achieves this by writing data in incremental blocks rather than in a single block. The most common file system for packet writing systems is the UDF
Universal Disk Format
Universal Disk Format is an implementation of the specification known as ISO/IEC 13346 and ECMA-167 and is an open vendor-neutral file system for computer data storage for a broad range of media. In practice, it has been most widely used for DVDs and newer optical disc formats, supplanting ISO 9660...

 format.

Deleting files and directories of a CD-R
CD-R
A CD-R is a variation of the Compact Disc invented by Philips and Sony. CD-R is a Write Once Read Many optical medium, though the whole disk does not have to be entirely written in the same session....

 using packet writing technology does not recover the space occupied by these objects but are simply marked as being deleted. Similarly, changes to files cause new instances to be created instead of replacing the original files. Because of this, the available space on a medium using packet writing technology will slowly diminish every time its content is modified. For rewritable discs, however, this doesn't necessarily occur; there exists technology that allows them to be used as truly removable storage media, fully and freely writable (see UDF
Universal Disk Format
Universal Disk Format is an implementation of the specification known as ISO/IEC 13346 and ECMA-167 and is an open vendor-neutral file system for computer data storage for a broad range of media. In practice, it has been most widely used for DVDs and newer optical disc formats, supplanting ISO 9660...

).

Due to the characteristics of optical rewritable media such as CD-RW
CD-RW
A CD-RW is a rewritable optical disc. It was introduced in 1997, and was known as "CD-Writable" during development. It was preceded by the CD-MO, which was never commercially released....

s and DVD-RW
DVD-RW
A DVD-RW disc is a rewritable optical disc with equal storage capacity to a DVD-R, typically 4.7 GB. The format was developed by Pioneer in November 1999 and has been approved by the DVD Forum. The smaller Mini DVD-RW holds 1.46 GB, with a diameter of 8 cm.The primary advantage of DVD-RW over...

s, the ability of data sectors to hold their contents wear out by changing them frequently (since re-crystallized alloy de-crystallizes). To cope with this the packet writing system can remap bad sectors with good sectors as required. These bad sectors cannot be recovered by formatting the media.

Software Packages

  • Drag-to-Disc (former DirectCD)
  • Nero InCD
    InCD
    InCD is a packet writing software developed by Nero AG for Microsoft Windows.InCD allows optical discs to be used in a similar manner to a floppy disk...

  • Drive Letter Access
    Drive Letter Access
    Drive Letter Access is a commercial packet writing application for the Microsoft Windows operating system that allows optical disc data storage devices to be used in a manner similar to floppy disks. DLA is a packet writing technology for CD and DVD media that uses the UDF file system.Roxio Burn...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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