KC 7.4 - Software Change Control

Software Change Control - The process by which a software change is proposed, evaluated, approved or rejected, scheduled, implemented, closed, and tracked

It is formally defined (IEEE610.12-90) as “A discipline applying technical and administrative direction and surveillance to: identify and document the functional and physical characteristics of a configuration item, control changes to those characteristics, record and report change processing and implementation status, and verify compliance with specified requirements.”

a & b. Project & Environment.

An effective software change request (SCR) process requires the use of supporting tools and procedures ranging from paper forms and a documented procedure to an electronic tool for originating change requests, enforcing the flow of the change process, capturing CCB decisions, and reporting change process information. A link between this tool capability and the problem-reporting system can facilitate the tracking of solutions for reported problems. Approved SCRs are implemented using the defined software procedures in accordance with the applicable schedule requirements. Since a number of approved SCRs might be implemented simultaneously, it is necessary to provide a means for tracking which SCRs are incorporated into particular software versions and baselines. As part of the closure of the change process, completed changes may undergo configuration audits and software quality verification. This includes ensuring that only approved changes have been made. The change request process described above will typically document the SCM (and other) approval information for the change.

c. Version Control.

Software items evolve as a software project proceeds. A version of a software item is a particular identified and specified item. It can be thought of as a state of an evolving item. A revision is a new version of an item that is intended to replace the old version of the item. A variant is a new version of an item that will be added to the configuration without replacing the old version.