This documentation is for WSO2 Complex Event Processor 4.0.0. View documentation for the latest release.
WSO2 Complex Event Processor is succeeded by WSO2 Stream Processor. To view the latest documentation for WSO2 SP, see WSO2 Stream Processor Documentation.

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For the relevant versions of the applications used as features, see Compatibility of WSO2 Products.



Extremely High Performant Processing Engine

  • Process about 100K+ events per sec second on single-server commodity hardware
  • Powered by WSO2 Siddhi

Powerful and Extensible Query Language for Temporal Event Stream Processing

  • SQL-like query language
  • Filter Filters events by conditions
  • Join Creates new event streams and create new by merging existing event streams
  • Execute Executes temporal queries using various windows
  • Detect Detects and respond responds to various event patterns and sequences
  • Instigates with In-Memory and RDBMS data stores for correlating historical data with real-time
  • Partitioning support to achieve parallel processing
  • Maintenance of execution plan templates
Easy to used User-friendly Execution Management
  • Suitable for business users to edit and manage realtime executions execution logic
  • Users interact with forms instead of with SQL Queries 
  • Queries and logics are templated to hide the complexity

Support for Rich Event Model

  • Events are modelled as tuples of metadata, correlation data and payload data.
  • Support for typed properties different property types including integral types, floating types, string and Boolean

Extremely High Performant Event Capturing and Delivery Framework Over Binary and Apache Thrift

  • Java data publisher agent to plug into any Java based system
  • Data publisher agent support in other languages (C/C++/C#) via Thrift language bindings
  • Horizontally scalable to support very large event volumes

Easily Integrates with any Enterprise System for Event Capture

  • RESTful HTTP protocol with JSON, XML and Text message formats
  • Map, JSON, XML and Text messages support via JMS
  • SOAP over any transport protocol
  • Kafka, MQTT, File, Websocket and Email protocols with JSON, XML and Text messages


Support Supports Multiple Alert Nitrifying Mechanisms

  • XML, JSON, Map, Text events via JMS protocol
  • E-mail, SMS notifications
  • Service calls to notify RESTful and Web services
  • MySQL and Cassandra writers
  • Kafka, MQTT, File, Websocket protocols supporting JSON, XML and Text messages alerts
IoT (Internet of Things) Integration
  • With MQTT protocol
Debugging Support
  • Event tracing, Event Flow visualization and Event Simulation capabilities
  • Siddhi TryIt to try out Siddhi queries

Massively Scalable

  • Distributed Real Time Processing
  • Support highly scalable deployments with Apache Storm and WSO2 Siddhi 
  • Deploys numbers of queries partitioning them into different servers

Highly Available Deployment

  • Run CEP in active-passive deployment with zero downtime
  • Coordinates event and state sharing

Support for Long Duration Queries

  • Queries can have lifetimes that are much greater than server uptime
  • Supported via HA deployment and persistence snapshot deployment
  • Support periodic snapshots that can store all state information and windows to a scalable persistence store
  • Pluggable persistent stores

Tightly Integrates with WSO2 Data Analytics Server

  • Leverage Lambda architecture to integrate post-processed data with real-time data processing
  • Support Supports recording and post processing of events with Map-Reduce via Apache Spark

Built-in Support for WSO2 Products

  • Pre-built event sources from other WSO2 products

Lightweight, Developer Friendly and Easy to Deploy

  • Server customization via provisioning of features
  • Deployment options from on-premise to private or public clouds, without configuration changes
  • Integrated with WSO2 Developer Studio, the Eclipse-based IDE for all WSO2 products

Manage and Monitor

  • Comprehensive management and monitoring Web console with enterprise-level security
  • Built-in collection and monitoring of standard access and performance statistics
  • Flexible logging support with integration to enterprise logging systems
  • In build support for rich representation of data through via a dashboard
  • Simulating capabilities via the Event Simulator.