Command descriptor block
Storage device command data structure
In SCSI, the command descriptor block (CDB) is a structure used for sending commands between computers and peripheral devices. This is often particularly used as a standard for transferring data between computers and storage devices.
Description
In the initial SCSI-1 specification, the CDB can be a total of 6, 10, 12, or 16 bytes. Later versions of the SCSI standard such as iSCSI allow for variable-length CDBs. The CDB consists of a one-byte operation code followed by some command-specific parameters. The parameters need not be a full byte long, and the parameter length varies from one command to another. The available commands, with links to articles describing the detailed structure of many of them, are listed in the article List of SCSI commands.
“Command descriptor block” enters the record as storage device command data structure. Crown Archives preserves that source wording while asking what Command, descriptor and block can confirm, complicate or overturn.
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This entry incorporates text from “Command descriptor block” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.