Information Technology Reference
In-Depth Information
solution immediately and benet from the supplier's economies of scale. Or at
least, you do if you select a well-established, reputable supplier. You also get
ongoing support, maintenance and periodic upgrades. However, such upgrades
can be a mixed blessing because they may introduce changes that invalidate
the way you have integrated the product into your system.
There is certainly no magic bullet in this area. The customer wants guar-
antees of product stability from the supplier, but the supplier has to balance
the conflicting demands that many different customers place upon them. They
also need to innovate to attract new customers. The balance between these
conicting requirements will depend on the nature of the supplier's business.
A supplier who uses a family of components to offer individually tailored, be-
spoke solutions to respond to individual invitations to tender from their cus-
tomers will be more likely to take account of individual customer constraints
than one selling a generic product in shrink-wrapped form to thousands or
even millions of customers.
A lot depends on the way the suppliers document their products, and how
seriously they take the maintenance of this documentation, on the provision of
advanced warnings of changes in the product and on the supply of transition
tools to make the customer's life easier. At the core of these documentation
issues is the need to create suitable models, both of the product and of the
way it is to be used; these models themselves need to be positioned within the
ODP framework.
12.2 Supplier and User Views
The supplier will have its own specifications used in designing and con-
structing the product, but these include much private detail, so we concen-
trate here on a set of models related to its use. These have a number of jobs
to do.
In an ideal world, the process of assessing the available products and de-
ciding which to use will involve confirming the relationships between these
various models (as well as many other factors involving value for money and
commercial credibility, of course). We illustrate these relations in figures 12.1
and 12.2, by showing the observable behaviour as Venn diagrams, so that
subsets of possible behaviour are shown as included within their supersets.
A product is suitable if the services it offers are a superset of those the user
requires, and if the infrastructure support available in the user's environment
is a superset of the product's requirements.
First, let us consider the infrastructure. The supplier will have a model,
in functional terms, that describes the infrastructure needed to support the
product; this model will, in general, describe several alternatives because it will
cover a range of different environments in which the product can be deployed.
