Controlling the Coverage of Grid Information Dissemination Protocols

Grid information dissemination protocols distribute information about the dynamic state of computational resources throughout interconnected wide area grids. Performance metrics for these protocols include the overhead of information packets, and the accuracy of the information at the time it is used to schedule applications. Our previous work advocated non-uniform protocols to keep dissemination local to the information source, as a method of keeping overhead manageable while achieving adequate freshness and accuracy. This paper considers the problem of providing better control over the dissemination of information and influencing the "coverage footprint" that defines where the information reaches within the grid. The paper describes work that investigates the coverage characteristics of existing protocols and refines and combines them into hybrid protocols that are more controllable. We consider this work to be a necessary step toward adaptive dissemination protocols that would be able to react to the state of grid resources to change dynamically how and where information is disseminated. This in turn increases the effectiveness of grid schedulers under various load levels and distributions