Introduction

The Decision Service Node in IBM® Integration Bus runs a J2SE runtime business rules engine which can process rules based on the business content from messages within integration bus flows. The runtime rules engine can come from the IBM Operational Decision Manager (ODM) product. The major benefits of doing this is it provides a rule authoring language understandable to both business and IT users, runs tightly coupled for high performance and reliability and provides an additional choice to all Integration Bus flow developers that they can author business rules in ODM as an alternative to ESQL.

IBM Operational Decision Manager (ODM), has the following major components:

IBM Decision Server is the runtime rule engine which will be tightly coupled with IBM Integration Bus to execute the required business rules for the message flow.
- IT users have the ability to author, test and deploy business rules using an Eclipse based tool called IBM Rule Designer (ILOG® Rule Studio in v7.1) which comes as part of IBM Decision Server (ILOG Rule Execution Server).
There is an optional Rule Governance and Business User component called the IBM Decision Center. It allows an enterprise to provide a controlled environment to improve collaboration between business and IT users, and enables business users to view, or to author and view business rules.

The recommended joint solution between IBM Integration Bus and IBM Operational Decision Manager is shown in the following figure.

Figure 1. IBM Integration Bus and IBM Operational Decision Manager solution

Simply adding the two products together in this tightly coupled J2SE configuration of ODM had some management limitations and restrictions in the Rule Engine being informed when rules were being updated. These were eliminated by the Decision Node Service capability by adding rule management capability to the J2SE engine using MBean events and management facility from J2EE engine. Both the Management/Authoring and runtime business rules engines work on a shared rule persistence layer (implemented as a database) to have a centralized single view of the latest business rules.

The Decision Service Node has two main processes which complement running the business rules

If a request enters a decision node, a rule request is generated and the request is issued against the decision server (Call rule set process).
If a rule is changed by the Decision Server Management Console an event thrown by the MBean Server and this updates by a listener the cached rule in the J2SE Decision Server of the Integration Bus (Update rule process).

A rule set is an ODM artifact which contains one or more individual rules and has pre-defined inputs and outputs which together provide the decisioning capability that the flow in Integration Bus requires at that point during the flow. Individual rules are not called directly.