Abstract: A client/server system is described incorporating methods for managing object availability through semantic object "load sets." By associating a particular "load set" with each object which might be requested by a client, improved object fetching and cache management is provided. Methods are described for managing object fetching and discarding on a per object basis, not on a per page basis. Each "semantic object" is packaged in a "storable," which incorporates dependency lists indicating the context in which the object is to be used (i.e., with which dependent objects). Additionally, a program developer can specify that the set of behaviors is defined at runtime, using "prefetch" primitives provided by the system. This allows an executing application to prefetch objects based on the then-existing dynamics of the system. With this approach, object availability in a distributed object environment (e.g., Internet) is improved.

Abstract: An Interactive Television (ITV) Client/Server system comprises one or more Clients (e.g., set top boxes or "STBs") connected to a Server module, via a Broadband Communication Network, is described. The system provides a generic mechanism for deciding how much or how little data is to be sent in response to a request from a Client. Specifically, each Client is allowed to describe ahead of time how much memory (approximately or exactly) it is allowing for the query result. This is communicated by the Client as part of the query itself. Regardless of what other activity the Client undertakes, the server maintains the context of the original query, until the Client terminates the connection. In a similar manner, when other simultaneous queries are open, the context is maintained for each query until the connection is dropped (or the query terminates). The Client can ask for more data (i.e., rows) on any open query. To optimize operation of the environment, requests from the Clients (i.e.