B2B Integration : A Practical Guide to Collaborative E-commerce

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provide a single-domain, single-vendor solution for transaction processing.
Stored procedures and triggers in single-vendor database environments
now handle many of the transactional duties that used to be performed
by TP monitors. However, these solutions lack such benefits as loadbalancing
and prioritization found in traditional application servers and TP
monitors. These vendor specific TP solutions can also prove inadequate
when considering that the typical Fortune 500 company has dozens of
separate databases based on four or more different database products.
TP monitors are a necessity in most database-centric integration
solutions. The major middleware vendors have not overlooked this fact
as the lines between application servers, distributed objects and TP
monitors are quickly becoming blurred.
A few leading vendors for transactional middleware include BEA's
Tuxedo, IBM's CICS and Microsoft's MTS.
8.3. Message Oriented Middleware (MOM)
MOM is an integration model that connects applications running on
different systems by sending and receiving application data as messages.
MOM is an asynchronous communication style that provides a loosely
coupled exchange across multiple operating systems and disparate
applications (see Figure 8.1).
Sender Receiver
Application A
Message
Application B
Message
Message! •
Sent! 1 Message
ip> (Received
Queue Manager
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as Mediator
Figure 8.1. — Asynchronous communication using message oriented middleware