Title: Overview
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Apache Airavata is a software toolkit currently used to build science gateways but that has a much wider potential use. It provides features to compose, manage, execute, and monitor small to large scale applications and workflows on computational resources ranging from local clusters to national grids and computing clouds. Gadgets interfaces to Airavata back end services can be deployed in open social containers such as Apache Rave and modify them to suit their needs. Airavata builds on general concepts of service oriented computing, distributed messaging, and workflow composition and orchestration.

### Airavata Components 

* XBaya Workflow Suite - includes a GUI for workflow composition and monitoring. The workflows can be interpreted at each step providing dynamic interactive capabilities. The composed workflow can be exported to various workflow languages like BPEL, SCUFL, Condor DAG, Jython and Java. The defacto workflow enacting engine used is Apache ODE.
* GFac - an application wrapper service that can be used to wrap command line-driven science applications and make them into robust, network- accessible services. This component is build on Axis2 web service stack.
* XRegistry - a registry service for storing deployment information about wrapped application services and constructed workflows.
* WS-Messenger - a publish-subscribe based message broker implemented on top of Apache Axis2 web services stack. It implements the WS-Eventing and WS-Notifications specifications and incorporates a message box component that facilities communications with clients behind firewalls and overcomes network glitches.