ITR/SI: Cooperative Computing for Distributed Embedded Systems

The objective of the proposed work is to develop an integrated computational-communication a chitecture

for large scale netwo ks of embedded systems,called cooperative computin .Unlike distributed comput-

ing,coope ative computing is pe formed ove a dynamic ad-hoc network with volatile nodes and connections,

and expects statistically correct executions.E .ective esource management,in pa ticula power and energy

management,will be c ucial since most devices in the netwo k will be mobile and will ely on batte y.The

basic idea in coope ative computing is that nodes coope ate in pe forming a global task in an ad-hoc manne

using thei local esou ces and state information to att act task 's computation o communication.Caching,

routing,topology discove y,o any speci .c use -de .ned application,can be implemented as a global task

over the cooperative computing model.

To effectively cooperate,the nodes that are involved need to know the esources and constraints they face

in successfully accomplishing the ta get task.In such a power and esource constrained environment,the

coope ating nodes must intelligently make the best decisions to ensu e the quality of esult (QoR).

With these goals in mind,the p oposed esea ch is to develop a system a chitectu e to support coope ative

computing ove dynamic netwo ks of embedded systems.Our resea ch will address the following issues:

How to de .ne a global task at the application and ope ating system levels?

How to prog am very large networks of embedded systems to execute a global task without handling

each node individually?

How to implement self-outing using peer-to-peer communication only?

How to measure a pa tially successful execution?

How to predict the powe dissipation and energy consumption of individual nodes,and nodes cooper-

ating ac oss the network?

How to optimize a task to reduce its powe and ene gy budget running on individual nodes,and across

nodes in network?

The system a chitectu e for coope ative computing is based on Smart Messages (SM),which can be

viewed as intelligent ca ie s of data in a netwo k.Sma t Messages a e collections of code and mobile data

that migrate th ough the netwo k,a single network hop at a time,executing at each step.Smart Messages

a e self-outing,namely they a e esponsible fo dete mining thei own paths th ough the netwo k,utilizing a

minimal set of facilities p ovided by nodes in the netwo k.An SM may be denied a equest to oute th ough

a node due to the node 's esou ce limitations,in pa ticula its emaining ene gy level.We conjectu e that

Smart Messages p ovide a .exible support for a wide variety of applications,anging from data collection

and dissemination,content-based outing and object t acking,to more t aditional dist ibuted computing

applications in which execution of a task is sp ead across a collection of devices.

As pa t of this p oposal we plan to implement and extensively evaluate seve al p ototype implementations

of the Smart Message a chitectu e.Ou testbed will consist of networks of embedded multicontrollers and

PDAs based on Bluetooth sho t-range wi eless communication.