Chapter 1 Overview : Runtime Architecture and Flow

Runtime Architecture and Flow
BusinessEvents has three layers of functionality:
Rules Evaluation and Execution  based on the state of objects, events and temporal aspects. This functionality is achieved by configuring one or more inference agents with the appropriate rule sets. Each inference agent maintains a Rete network to remember past matches.
Lifecycle Management of Objects and Events  including distribution, clustering, persistence and recoverability. Various options are available to achieve the levels of functionality appropriate for business needs, from in-memory only storage of objects, to advanced caching features and a backing store (database).
Querying the Cache  A query agent (not shown below) is an optional component available in TIBCO BusinessEvents Enterprise Suite. It enables visibility into cache data and enables cache data to be returned and used in BusinessEvents or externally.
Figure 1 TIBCO BusinessEvents Architecture
Rule Evaluation and Execution
Information from enterprise applications and other sources flows into BusinessEvents through channels as messages. BusinessEvents transforms messages to events, based on event definitions (event types) and asserts them into working memory.
All the rules whose conditions match information in the events are assembled into a rule agenda and the first rule executes. Rule actions create and modify the facts, which are processed into a structure known as a Rete network, an in-memory network of objects based on the Rete algorithm which enables fast matching of facts with rule dependencies.
BusinessEvents uses a forward-chaining inferencing engine, based on the Rete algorithm. Every time the facts change—due to rule actions or the arrival of new information—the inferencing engine updates the rule agenda. The process goes on until there are no more changes to process. This is known as a runt o completion cycle or RTC. See Understanding Conflict Resolution and Run to Completion Cycles for more details
(Note that State Machine, is present only in TIBCO BusinessEvents Enterprise Suite).