Enterprise Application Integration (EAI) - Guide to Cloud Computing for Business and Technology Managers - page 103

and integrates applications at a higher level of abstraction. SOA, BPEL, and
related technologies today provide new opportunities for making inte-
grated information systems more flexible and adaptable to business process
changes. This way, our information systems can get more agile, provide bet-
ter support for changing requirements, and align closer to business needs
(see Chapter 10, “Service Composition”).
4.2.2.5 Business-to-Business Integration
There is a growing need to enable inter-enterprise integration, often referred
to as business-to-business (B2B) integration, or e-business. The requirements
today for online, up-to-date information, delivered with efficiency, reliabil-
ity, and quality, are very high and gone are the days where a company could
just publish offline catalogs on their Web pages.
Customers today expect immediate response and are not satisfied with
batch processing and several days of delay in confirming orders. However,
these delays are often the case when e-business is not backed by an effi-
ciently integrated enterprise information system. Immediate responsiveness,
achieved by the highly coupled integration of the back-end (enterprise infor-
mation systems) and the front-end (presentation) systems, is a key success
factor. Nonintegrated systems fail to meet business expectations; the primary
reason for this is the lack of enterprise integration. In an e-business scenario,
Applications from one company are invoking operations on front-end appli-
cations belonging to other companies. Only if these front-end systems are
satisfactorily connected with back-end systems can the other company be
able to provide an immediate and accurate response, which is an essential
prerequisite for successful B2B collaboration.
4.2.3 Patterns of Integration
Integration patterns can be grouped into point-to-point integration and hub-
and-spoke integration based on the way applications are connected. In the
first approach, the applications are directly connected, while in the second,
message exchanges go through a third party before being delivered to the
final destination.
4.2.3.1 Point-to-Point Integration
Point-to-point integration is the simplest way to integrate independently
developed application silos and do not require significant upfront invest-
ment. Each application is connected directly and explicitly to others. To link
each application to another directly, an interface needs to be developed.
This style may work well if the number of applications to be integrated is
not large and there is no intention to scale out. Otherwise, it may quickly