scope:

The SCSI family of standards provides for many different types of SCSI devices (e.g., disks, tapes, media changers). This standard defines a device model that is applicable to all SCSI devices. Other command standards expand on the general SCSI device model in ways appropriate to specific types of SCSI devices.

The set of SCSI standards specifies the interfaces, functions, and operations necessary to ensure interoperability between conforming SCSI implementations. This standard is a functional description. Conforming implementations may employ any design technique that does not violate interoperability.

This standard defines the SCSI commands that are mandatory and optional for all SCSI devices. Support for any feature defined in this standard is optional unless otherwise stated. This standard also defines the SCSI commands that may apply to any device model.

The following commands, parameter data, and features defined in previous versions of this standard are made obsolete by this standard:

a) the printer device type;

b) the write-once device type;

c) all features specific to SPI-5 (e.g., fields in the standard INQUIRY data);

d) Power Conditions management that is specific to SAS-2;

e) ACCESS CONTROLS well known logical unit;

f) ACCESS CONTROL IN command;

g) ACCESS CONTROL OUT command;

h) Capability-based Command Security;

i) CbCS extension descriptor;

j) RECEIVE CREDENTIAL command;

k) all requirements for the one-byte third-party copy list identifier (leaving only the four-byte identifier);

l) the space function segment descriptor for the EXTENDED COPY command;

m) the locate function segment descriptor for the EXTENDED COPY command; and

n) the ability to manage thresholds in log parameters using the TMC field and ETC bit.