SSADM is a relatively little-used approach sponsored by
the British government. It is based on Shlaer-Mellor notation with some extensions to cover Entity-
Relationship modeling, and state machines. It supported by a toolset. See www.webpoedia.com/TERM/
S/SSADM.html for more.
4.4.6 Synch and Stabilize
This is an approach favored by Microsoft. It consists of three phases: planning (specification and review),
development (several ??” usually 3 ??” subphases developing feature sets of decreasing priority plus a
period of optimization), and stabilization (beta test and finalization). The process is characterized by
feature teams consisting of 3??“8 programmers, (an equal number of) testers, and technical writers who
work jointly on a feature. Microsoft planning allows for a buffer time of between 20??“50% of the total
project time to allow for unplanned events.
The coherence of each feature is underpinned by a nightly build in which much social opprobrium
attaches to the programmer whose code ???breaks the build.??? Each build (however incomplete) is regression-
tested. Testers are thus kept very close to evolving features. Internal testing is then augmented by
external testing by off-shore suppliers and friendly customers. See section 18.9.6 for some statistical
justification of this approach.
Managing this test process requires that:
??? Staffing levels are comparable to Microsoft??™s. Thus in addition to the 1: 1 developer-tester ratio
you will need a further backup of off-shore testers.
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