Testing Strategy - Software Testing: Testing Across the Entire Software Development Life Cycle - page 75

If all of the support layers for the application under development have been used
successfully many times by the developers, then the support layers are considered
“trusted,” and only cursory test planning is necessary to reverify their “trustedness.”
If any of the support layers are new to development (and production by
implication), then you need to seriously consider a full test plan for that support layer
and all support layers above it. Strongly consider testing the support layers as far in
advance of the application under development coding as possible. If the new support
software layer does not pass all verifi cation tests, the developers could be forced to
redesign their application in mid-stream to use different support software … that
should likewise be tested before redevelopment is too far along.
Popular approaches for designing e-business software have presented the support
layer testing strategist with a new dilemma. The design of the new e-business soft-
ware may rely on trusted support layers, but the combination of trusted components
is new to development and production. A cautious, conservative testing strategy is
recommended. Consider testing the new support combinations more thoroughly
than if they were truly trusted but less thoroughly than if they were completely new
components. Test key features and functionality that the application under develop-
ment must rely on. If no issues arise, complete the testing at a cursory level. If issues
arise, deepen the testing effort to help the developers quickly formulate a go/no go
decision with this support combination.
4.4 THE THREE-DIMENSIONAL TESTING STRATEGY
CHESS BOARD
The internet has matured as a viable business marketplace. Part of that internet
maturing process has been the implementation of successively larger, more com-
plex e-business applications. At fi rst blush, it would appear that you need a whole
new set of testing skills and strategies to test these e-business applications. A closer
examination of the situation reveals that over 95% of the testing skills and strategies
used for traditional (non-e-business application) testing are still viable. The 5% new
testing skills and strategies will be discussed in Chapter 14.
The best way to apply the 95% of testing strategies that you already know to
e-business applications is to add a third dimension to the testing strategy chess
board. This third dimension will represent the multiplicity of software platforms
that e-business applications typically use.
4.4.1 Software Platforms—The Third Testing
Strategy Dimension
Let us look at some examples of software platforms from a testing strategy per-
spective. Consider the grouping of all business computers into three categories:
workstations, networks, and servers.