[e2e] Data flow models for real-time applications

[Craig Partridge]

In message <499BC4E0.7050202 at tm.uka.de>, Christoph Mayer writes:

>> Either that, or make the sensors a tiny bit smarter. I am sure there are lot
 >s of publish papers on how to make distributed systems like these more effici
 >ent, e.g. have a varying fraction of the sensors activated at some time, with
 > the fraction varying based on activity level...
>
>if anyone is aware of papers that go into this direction I would be very 
>interested! I currently start looking into what network traffic will 
>look like in the "Internet of Things". Imagining sensors, tags, etc. 
>everywhere in our environment and all of them communicating ... this 
>will maybe change the traffic characteristics in Core/Edge networks 
>dramatically. I am happy on any ideas into this direction.

I can't seem to call up the papers off hand but let me suggest some
directions.

There are papers on how to make sensor networks more effective at getting
information to a collection point.  The usual hard problem is that you
assume a field of sensors, and someone/something passes by and wants to
be told what the sensor net has learned.  The simple version is the collector
send out a query, which gets flooded (easy, a tree out from the sensor
node the collector is closest to), and the answers flood back (up the
tree to the root) and overwhelm the sensor network near the collector.
Various papers on summarizing reports along the way back, etc.
I think you may find the Sensys proceedings a good place to dig on this
topic.

I don't know if he's published it, but John Doyle of CalTech pointed out
to me last fall that if you look at biological networks for inspiration,
there's an alternative approach.  In bio networks (such as how the body
gets inputs from your eyes), there's apparently often an order of magnitude
more bandwidth from collector to sensor than from sensor to collector.
So imagine that the collector instead of saying "what do you know?" says
"have you observed events of the following types in the following time
ranges?" and only hears from sensors for which the answer is "yes".

Hope this is useful!

Craig