A schedule is
a sequence of activities (both system and manual) that can be planned
together. It is the response to a trigger event.
A schedule
can be further described by a series of macro level tasks. Each of these
tasks can fulfil a goal of a user (and thus can be standalone in its own
right). From a user’s perspective they are black box. Thus a schedule can
be perceived as a broader end to end process.
Tasks are a
composites of low level activity – which is defined as something that
actually does something (a set of code being executed, or a person
performing something) and has a result. By allowing both the system and
human duties being performed in the same end-to-end the schedule can
fulfil the responsibilities of a classic workflow (or job management)
The building
blocks of a schedule are thus:
 | Schedule
|
 | Tasks
|
 | System Activities
|
 | Manual Activities
|
This can be
modelled as is shown here, with a business example of each (note this
examples is built upon as we go along and is concluded with a detailed
version):

These
activities can be:
 | Real-time |
 | Batch |
To a large
extent the flow of events is very similar to those of in both cases, but
generally speaking:
 | For event driven the
trigger is often unpredictable, the execution is perceived real-time and
is performed on a individual logical transaction, |
 | For batch driven the
trigger tends to be predictable (a 10pm trigger is after all certain to
occur), the execution has a processing window, and is performed on a
often large group of logical transactions. |
But these are not hard and fast rules - since even event driven processes
could be designed to have a predictable trigger - for example it may be
desirable to only initiate the accept trade task between certain hours,
the start and end could be defined as temporal triggers.


©
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,
Dale Hill Cottage, Kirby-Le-Soken, Essex CO13 0EN,United Kingdom.
Telephone: +44 (0)1255 862354/Mobile: + 44 (0)7710 435227/e-mail: info@codel-services.com