Dependency on Events
In the previous
model all three “levels” of the schedule definition share common behaviour
in one respect – they all have dependencies – i.e. events that must occur.
Except for schedules and tasks these are primary, and for activity
secondary.
Although we can
visualise the tasks being “strung” together, what is actually happening is
the task knows its trigger event – which could be based on a previous task
being completed, or some external event – as far as the task goes it
“doesn’t care”. The dependency of events are thus either:
 | Primary Events
(Those that exist outside the system domain) |
 | Secondary Events
(Those that occur as a result of or within system domain) |
Our model now looks
like….

Applicability
This is an important
concept and allows a single
definition to works at both generic and specific levels
For example
the End of Day (EOD) schedule for Bonds
may be similar to Swaps for an organisation e.g. the have the same
triggers (if this wasn’t the case there would be no realistic basis for a
generic system). The trigger values will be different for Bonds and Swaps
… something we will come to this later…
Routing
logic
Dependency thus allows for both:
 |
Routing Logic (Planned
flow based on different conditions) |
 |
Exception handling (Planned
response to failure) |
Routing logic allows
for separate dependencies based on the outcome of an activity, the
applicability or the pass/fail states to be defined, or what the activity
has done (e.g. get me an algorithm) (although as discussed later these
will have different implementations).
Routing can also be
in series and parallel
Now we will look at a worked example, extending some of the themes we have
discussed.


©
2002-2005 Codel Services Ltd
This paper has been prepared
by Codel Services Ltd to illustrate how structured business
modelling can help your organisation. Codel Services Ltd is an IT
Consultancy specialising in business modelling. If you would like further
information, please contact us at: Deryck Brailsford, Codel Services Ltd,
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