Diploma Thesis, TU-Vienna, 2008

With a continuously growing number of computers that are connected over distributed networks, in particular the internet, there is also a growing need for applications to communicate with each other over these networks. Following the idea of shared data spaces, XVSM (eXtensible Virtual Shared Memory) provides a middleware solution that allows applications to collaborate with each other in an easy and natural way without the need of a central server. XVSM specializes in the coordination of data, providing flexible data structures for all different kinds of communication, which most other shared data space implementations lack. Despite of that, XVSM aims to be very light-weight, and at the same time provide a great amount of extensibility for easily adding features that are not initially a part of XVSM.

 

This document focuses on the XVSM core, which is the software component that implements XVSM, and introduces its architecture in detail, which aims to provide concurrency, scalability and extensibility for all the features defined in the XVSM model. An implementation of this model is shown with XcoSpaces, the .Net reference implementation of XVSM, which has been built following the introduced XVSM core architecture. It is also shown how XcoSpaces has been built as a component oriented architecture that greatly supports the extensibility of the XVSM model from an implementation point of view.

 

For proving how easy it is to add additional functionality to XVSM, it is shown with XcoSpaces how new features are added that enable simple security mechanisms for the space.