Caching of objects in the World Wide Web is a widely used technique to reduce end user latencies, network and server load. Currently deployed heuristic-based approaches to caching are not ideal, and prior results show potential for better reuse of cached Web content. This work studies a more deterministic approach to caching of Web objects where Web servers supply more complete information to client caches about the objects served. The idea is to view container (HTML) objects as a collection of distinct objects with heterogeneous change characteristics. Relationships between these and embedded objects (images) can be exploited at the server side. Servers can generate cache invalidation information and piggyback it onto existing request/resp...