The Medusa applications environment

Medusa is a peer to peer architecture for controlling networked multimedia devices. This paper describes the software model presented to the applications programmer. Active objects called modules are used to represent cameras, displays, format converters and so on. Data can flow from module to module on connections between them. We introduce two key ideas: firstly, connections between modules are simple, reliable and unbuffered. More complex connections are represented by special intermediate modules. Secondly, security is provided by naming modules with unforgeable capabilities then using hierarchies of proxy modules to restrict access