Virgo and Ocean Observatories Initiative

Virgo seems to be finding its way into the scientific community. A research hospital and a networking research group already use Virgo heavily. It seems that an oceanography group are also considering Virgo for their "ioncore-java" runtime.

They are at the stage of comparing various application servers. The front-runners, at least in terms of their feature comparison table, are Virgo and WSO2. Fortunately, I believe the architecture and design of these products are quite different, so this should make the decision easier.

Virgo was built from the ground up as OSGi bundles and offers first class support for OSGi applications. The Virgo kernel is independent of any particular communications protocol. Tomcat is added as part of the Virgo web server which sits on top of the kernel. The whole of Virgo runs inside an OSGi container. Web services can be supported on Virgo, but it's not something Virgo has majored on as this is just one of the features available in the Spring portfolio running on Virgo.

WSO2 on the other hand is focussed on - and the clue's in the name here - web services. It is constructed as an interoperating network of web services components. WSO2 does support OSGi, but it hosts an OSGi container inside Tomcat.

Let's see what the Ocean Observatories Initiative regard as the key requirements for their component model. If it's OSGi components with primarily local communication (i.e. Java method call), then I reckon Virgo would be ideal. If on the other hand they want a primarily distributed component model (and it's a big if) with web services as the communication protocol, then WSO2 may be a good choice.

One last word. I felt a bit sorry for Glassfish as it didn't get a tick in the J2EE box even though it's the J2EE reference implementation. Also Tomcat is the servlet engine used by Virgo, so it deserves just as much of a J2EE tick in the box as Virgo. Similarly JBoss should get the J2EE tick.