Defining the next generation repository
ResourceSync
ResourceSync is a specification based on Sitemaps that can be used by repository managers to provide information that allows third-party systems to remain in sync with the resources in their repository as they evolve, i.e. are created, updated, deleted. Whereas basic Sitemaps allow exposing a repository inventory and crawl-related metadata, ResourceSync adds ways to expose changes only, and to provide expressive synchronization-related metadata as well as typed links for further discovery. ResourceSync can be used for discovery and synchronization of both content and metadata and uses the Sitemaps XML format. http://www.openarchives.org/rs/toc