Event Stream Processing

Event Stream Processing, or ESP, is a set of technologies designed to assist the construction of event-driven information systems. ESP technologies include event visualization, event databases, event-driven middleware, and event processing languages, or complex event processing (CEP). ESP deals with the task of processing multiple streams of event data with the goal of identifying the meaningful events within those streams, employing techniques such as detection of complex patterns of many events, event correlation and abstraction, event hierarchies, and relationships between events such as causality, membership, and timing, and event-driven processes.

ESP enables applications such as algorithmic trading in financial services, RFID event processing applications, fraud detection, process monitoring, and location-based services in telecommunications.

Example

This example of an EPL (Event Processing Language) modelled on SQL illustrates how such a language may be used to perform complex event processing. This code fragment detects weddings among a flow of external "events" such as church bells ringing, the appearance of a man in a tuxedo or morning suit, a girl in a flowing white gown and rice flying through the air. A "complex" or "composite" event is what one infers from the individual simple events: a wedding is happening.

WHEN Person.Gender EQUALS “man” AND Person.Clothes EQUALS “tuxedo” FOLLOWED-BY Person.Clothes EQUALS “gown” AND Church_Bell OR Rice_Flying WITHIN 2 hours ACTION Wedding

ee also

* Complex Event Processing (CEP) A related technology for building and managing event-driven information systems.
* Real-time computing ESP systems are typically real-time systems
* RFID Radio Frequency Identification, or RFID, requires ESP
* SCADA Supervisory Control And Data Acquisition, a similar technology used in engineering applications
* High frequency computing

References

* [http://www.cs.brown.edu/research/aurora MIT/Brown/Brandeis "Aurora" Stream Processing Project]
*"The Power of Events" by David Luckham (ISBN 0-201-72789-7), from Stanford University, a book on CEP.
* [http://www.rfidjournal.com/article/view/1196 Separating the Wheat from the Chaff] Article about CEP as applied to RFID, appeared in RFID Journal
* [http://www.complexevents.com Complex Event Processing] - A source of industry neutral information on applications, research, usecases, reference architectures, and developments in event processing, run by Prof David Luckham

External links

* [http://esper.codehaus.org Esper - Open source implementation of CEP and ESP in Java]
* [http://wiki.open-esb.java.net/Wiki.jsp?page=IEPSE Open source implementation of ESP (IEP = "intelligent event processing")]