Integration Technologies - Guide to Cloud Computing for Business and Technology Managers - page 120

Integration brokers consist of components that provide the following
functions:
• Message transformation: The message transformation functionality
understands the format of all messages transmitted among applica-
tions. This is possible since the integration broker holds a reposi-
tory of schemas of interchanged messages. Using this knowledge,
the broker can translate between schemas by restructuring the data
of these messages. In this way, subscribing applications can make
sense of received messages.
• Business rules processing: The integration broker allows the applica-
tion of business rules to messages so that new application logic can
reside within the integration broker.
• Routing services: The routing functionality takes care of the flow
control of messages.
• Naming services: The directory services functionality is needed
since integration brokers function in a distributed environment and
need a way to locate and use network resources. Applications using
the integration broker are able to find other applications or hardware
on the network.
• Adapter services: Many integration brokers use adapters as layers
between the broker and large enterprise's back-end information sys-
tems to convert the data formats and application semantics from the
source application to the target application. Adapters map the differ-
ences between two distinct interfaces: the integration broker inter-
face and the native interface of the source or target application. For
instance, an integration broker vendor may have adapters for sev-
eral different source and target applications (such as packaged ERP
applications), adapters for certain types of databases (such as Oracle,
Sybase, or DB2), or even adapters for specific brands of middleware.
• Repository services: Repository houses information on rules, logic,
objects, and metadata on target and source applications. The reposi-
tory keeps track of input/output to the applications, its data ele-
ments, interrelationships between applications, and all the metadata
from the other subsystems of the broker like the rules processing
component. Metadata is one of the key elements of any integration
solution as it is used to describe the structure of information held in
disparate systems and processes.
• Events and alerts: Messages passing through the integration broker
may trigger events or alerts based on specified conditions. Such con-
ditions may be used for tracking business processes that move out-
side the range of given parameters and create a new message, run a
special-purpose application, or send an alert.