In
the case of legacy host applications, all three layers
are typically inextricably bound together, making
it complex, time-consuming, and even impossible to
separate and/or distribute the layers for integration
purposes.
What's
important to note up-front is that the first two approaches
are non-invasive, requiring no modification
to host applications. By contrast, the last three
approaches are invasive, requiring modification
and even replacement of host applications. When weighing
the options, it's also important to understand that
the approaches get progressively more costly and time-consuming
as you go from refacing to replacing.
The
merits or desirability of each approach depends upon
the unique business and technology scenario surrounding
each individual enterprise application in your portfolio.
You may, for instance, pursue one approach for one
group of applications, another for another group,
and yet another for a third group. Over time, you
may opt to change your approach with certain applications
in response to changing business needs.
The
Business Benefits Of Integration
Here
are just some of the benefits from integration:
