From IEEE Software Engineering Standards Collection:
IEEE Std 1074. This standard defines the set of activities that constitute the processes that are mandatory for the development and maintenance of software. The management and support processes that continue throughout the entire life cycle, as well as all aspects of the software life cycle from concept exploration through retirement, are covered. Associated input and output information is also provided. Utilisation of the processes and their component activities maximises the benefits to the user when the use of this standard is initiated early in the software life cycle. This standard requires definition of a user’s software life cycle and shows its mapping into typical software life cycles. It is not intended to define or imply a software life cycle of its own.