Synchronize And Stabilize Model

Synchronize and stabilize method combines the advantages of the spiral model with technology for overseeing and managing source code. This method allows many teams to work efficiently in parallel. This approach was defined by David Yoffie of Harvard University and Michael Cusumano of MIT. They studied how Microsoft Corp. developed Internet Explorer and Netscape Communications Corp. developed Communicator, finding common threads in the ways the two companies worked. For example, both companies did a nightly compilation (called a build) of the entire project, bringing together all the current components. They established release dates and expended considerable effort to stabilize the code before it was released. The companies did an alpha release for internal testing; one or more beta releases (usually feature-complete) for wider testing outside the company, and finally a release candidate leading to a gold master, which was released to manufacturing. At some point before each release, specifications would be frozen and the remaining time spent on fixing bugs. Both Microsoft and Netscape managed millions of lines of code as specifications changed and evolved over time. Design reviews and strategy sessions were frequent, and everything was documented. Both companies built contingency time into their schedules, and when release deadlines got close, both chose to scale back product features rather than let milestone dates slip.