Testing IT | 39
Alternatively, innovation may be in the for this approach: it is possible to take
form of new approaches to testing. advantage of advances in technology
For example, power consumption and also the pain associated with
and other environmental factors supporting legacy applications is
cannot be ignored for large system removed.
implementations and a trade-off The third approach is to enable one
may need to be done between user IT estate to talk to the other. This is
experience in the form of response done by writing bespoke interfaces
times and the power used by the and creating potentially complex
main servers. business processes. The advantages of
this are that one of the IT systems is
Merging existing and left relatively unchanged.
acquired IT estates The final approach would be to
There are essentially four approaches enable both systems to be able to
to merging IT estates. These are talk to each other. This rapidly leads
summarised in figure 2. to large numbers of interfaces and
The first approach is for one IT estate complex business processes that
SOA provides all of to swallow the other one. Like a large need to be managed. Fortunately,
the advantages of the
python swallowing a large mammal developments in service oriented
it can take quite a long time to digest architecture (SOA) allow for a
other approaches by
another IT estate. The larger the estate standards based approach to be used.
allowing some parts to be
that is ‘swallowed’ the greater the SOA provides all of the advantages
replaced, selecting one pressure on the existing systems eg of the other approaches by allowing
of the existing processes
much larger databases or significantly some parts to be replaced, selecting
if there is a clear winner
higher concurrency. one of the existing processes if there
The next approach is to use both is a clear winner and allowing different
and allowing different
IT estates only as a reference point technology stacks to talk to each
technology stacks to talk for defining a brand new system. other.
to each other.
This ‘Genesis’ approach happens It should be noted that SOA is
frequently. There are two advantages essentially a strategic move for a
T.E.S.T | June 09 June 09 | T.E.S.T
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