Take any integration project and you have multiple applications talking over multiple transports on multiple platforms. As you can imagine, in large enterprise applications this can get complex very fast. Much of the complexity stems from two issues:

1.  dealing with the specifics of applications and transports, and

2.  coming up with good solutions to integration problems.

continue reading here: http://java.dzone.com/articles/open-source-integration-apache

Useful links:

– http://camel.apache.org/
– http://stackoverflow.com/questions/8845186/what-exactly-is-apache-camel
– https://github.com/CamelCookbook/camel-cookbook-examples
– https://github.com/FuseByExample?page=2
– http://saltnlight5.blogspot.gr/2013/08/getting-started-with-apache-camel-using.html