[net2-wg] Proposal for dissemination structure and interfaces

[Philip Levis]

On Thu, 2005-12-29 at 17:10 -0500, Kyle Jamieson wrote:
> > If you have separate Update and Value components, then you need to
> > orchestrate the underlying instantiation.
> 
> Wouldn't there be at most one of the two types of component running on
> each base station and sensor node at once?  Or am I perhaps missing a
> situation where we would need both types of component running at the
> same time?

Here's a case I ran into in a projects class I taught last Fall. The
application was a fire rescue system. Motes form an ad-hoc tree to
stream status to a root. They have smoke detectors attached. When one
detects a fire, it triggers all other nodes into a danger state. Start
sampling faster, etc.

We wrote a hand-coded solution, but you could do this with
dissemination. A node detecting smoke updates the shared danger state
variable, propagating the result to everyone else. You also want to know
when smoke has been detected.

Phil