Question: We are developing an application integrator which sends requests to various webservices simultaneously, aggregate data return by each webservice and format it to display on UI. Each webservice may have proprietary xml format. Also we don't wont to compromise user experience.

We identified ESB(Servicemix/Mule) and Async Http Client for this requirement.

Can anyone suggest which would be better option? Async Http Client seems good fit as it is lightweight over servicemix.

Thanks,
Amit Patel

Answer: 
you can also just use [Apache Came](http://camel.apache.org)l for this...

It supports a wide range of [components](http://camel.apache.org/components.html) and [messaging patterns](http://camel.apache.org/enterprise-integration-patterns.html), is lightweight and has a flexible deployment model (standalone, spring, maven, webapp, OSGi, etc).
As per your requirement, I would suggest you to go with WSO2 ESB. Its and 100% free and open source ESB (Apache License 2) and unlike other ESBs, with wso2 you don't have the commercial and community versions. So, what you [download for free](http://wso2.org/downloads/esb) from WSO2, comprises of all the features that are available in 'commercial versions' of other ESB vendors. Also, WSO2 offers not just an ESB but a complete SOA Platform for your SOA needs.

For the requirement you mentioned above, there is a [simple sample](http://wso2.org/library/articles/2011/01/wso2-esb-by-example-service-chaining) that you can try out.