Replaced/Superseded by document(s)
The System/Subsystem Specification (SSS), or just System Specification, specifies the requirements
to be satisfied by a system, subsystem, HWCI, component or other item and optionally the
requirements for evidence that each requirement has been so satisfied. Requirements pertaining to the
system, subsystem or item’s external interfaces may be presented in the SSS or in one or more
Interface Requirements Specifications (IRSs) or Interface Control Documents (ICDs) referenced from
The SSS, possibly supplemented by IRSs or ICDs, is used as the basis for procurement, design,
qualification testing and acceptance testing of the system, subsystem or other item. Throughout this
DID, the term “system” may be interpreted to mean "segment", "subsystem", "element", "HWCI",
component or other item, as applicable. The resulting document should be titled System
Specification, Segment Specification, Component Specification or similar, as applicable, or a
corresponding subject matter – specific name, eg. “Air Traffic Control System Specification”,
“Specification of Power Supply Module”, etc.
This Data Item Description (DID) may be cited in a Statement of Requirement (SOR), Statement of
Work (SOW), a Contract Data Requirements List (CDRL), within a standard invoked by a SOR or
SOW, or within a plan, policy document or procedure.
This DID incorporates and adopts some non-copyrighted material contained in a System/Subsystem
Specification (SSS) DID issued by the United States Government.