The World-Wide Telescope (WWT) is a virtual observatory that federates astronomy and astrophysics databases at a global scale, with the ultimate goal of unifying all on-line data and making it available to everyone from everywhere. It dramatically improves the ability to perform multi-spectral and temporal studies by allowing researchers to access many databases with a single query. In its current form, increasing the number of sites and users in the WWT leads inevitably to a network crisis. As data-intensive scientific applications increase in scale, bandwidth constrains the performance of all applications sharing a network. As more scientists and educators adopt and rely on the WWT, the increased bandwidth requirements will degrade the performance of all applications. Federations need to focus on being good "network citizens," using shared resources conscientiously. If not, the workloads generated by these applications will make them unwelcome on public networks.
To avert the network crisis, this project will develop and release an open-source, commodity caching appliance based on two crucial technologies: bypass-yield caching and self-organizing database storage. Bypass-yield caching is an altruistic caching framework for scientific database workloads that balances parallelism in federations against the benefits of caching. It adopts "network citizenship" as its principal goal -- caching in order to minimize network traffic. Database caching introduces an acute storage management problem for which traditional administration is inappropriate. The dynamic creation and destruction of tables in a cache requires automated, incremental storage management with low space overhead. Self-organizing database storage automates storage management and database organization, turning the cache into an administration-free appliance.
Caching appliances are an enabling technology, making it possible for the WWT to accept a large number of users without impeding the performance of shared networks. Open-source software and commodity hardware make the acquisition of the appliance inexpensive and the self-organization of the cache makes it maintenance-free. The caching appliance will enhance astrophysical and astronomy research, making it possible for scientists to conduct experiments and find correlations across heterogeneous data sets at previously unforeseen rates. The WWT and the caching gateways will also bring telescope research and education to communities of users for which it was previously unavailable, particularly undergraduates and high school students. Project plans include outreach in the form of a pilot program that will install and maintain WWT gateways at high schools, colleges, and science museums and libraries, and assist those institutions in curriculum development.
