Requirements Analysis: System/Subsystem Specification (SSS)

The System/Subsystem Specification (SSS) specifies the requirements for a system or subsystem and the methods to be used to ensure that each requirement has been met. Requirements pertaining to the system or subsystem’s external interfaces may be presented in the SSS or in one or more Interface Requirements Specifications (IRSs) (DI-IPSC-81434A) referenced from the SSS.

The SSS, possibly supplemented by IRSs, is used as the basis for design and qualification testing of a system or subsystem. Throughout this Data Item Description (DID), the term “system” may be interpreted to mean “subsystem” as applicable. The resulting document should be titled System Specification or Subsystem Specification (SSS).

This DID contains the format and content preparation instructions for the data product generated by specific and discrete task requirements as delineated in the contract.

This DID is used when the developer is tasked to define and record the requirements to be met by a system or subsystem.

Requirements pertaining to system or subsystem interfaces may be presented in the SSS or in IRSs.