What happens when long-held assumptions are challenged
Many-to-Many Invocation (M2MI) is a new paradigm for building collaborative systems that run in wireless proximal ad hoc networks of fixed and mobile computing devices. M2MI is useful for building a broad range of systems, including multiuser applications (conversations, groupware, multiplayer games); systems involving networked devices (printers, cameras, sensors); and collaborative middleware systems.
One of the most common metaphors in OOAD clashes with the physics of the real world. Moreover, this clash isn't obvious in everyday systems - it only becomes obvious in a category of systems called "high risk systems." The metaphor is that of designing an object model that is isomorphic to the hardware aggregation hierarchy, i.e., decomposition by subsystem and device, with encapsulated state. Hardware units seem like obvious candidates for objects; the paper shows how this 'obvious' metaphor breaks down and can lead to a messy design. The paper uses examples from NASA space missions involving control of spacecraft and Mars rovers as examples of high-risk systems.
Participants should be ready to think outside the box.