Master SOA Design
Pattern Catalog
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Intermediate Routing
(Little, Rischbeck, Simon)
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Home > Service Messaging Patterns > Intermediate Routing
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How can dynamic runtime factors affect the path of a message?
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Problem
The larger and more complex a service composition is, the more
difficult it is to anticipate and design for all possible runtime
scenarios in advance, especially with asynchronous, messagingbased
communication.
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Solution
Message paths can be dynamically determined through the use
of intermediary routing logic.
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Application
Various types of intermediary routing logic can be incorporated
to create message paths based on message content or runtime
factors.
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Impacts
Dynamically determining a message path adds layers of
processing logic and correspondingly can increase performance
overhead. Also the use of multiple routing logic can result in
overly complex service activities.
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A message passes through two router agents before it arrives at its destination. The Rules-Based Router identifies
the target service based on a business rule that the agent dynamically retrieves and interprets, as a consequence of
Rules Centralization. The Load Balancing Router then checks current usage statistics for that service before
it decides which instance or redundant implementation of the service to send the message to.
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This page contains excerpts from:
SOA Design Patterns by Thomas Erl
Foreword by Grady Booch
With contributions from David Chappell, Jason Hogg, Anish Karmarkar, Mark Little, David Orchard, Satadru Roy,
Thomas Rischbeck, Arnaud Simon, Clemens Utschig, Dennis Wisnosky, and others.
(ISBN: 0136135161, Hardcover, Full-Color, 400+ Illustrations, 865 pages)
For more information about this book, visit www.soabooks.com.
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