A communication system for retrieving content stored in a content server is disclosed. The first connector includes a first terminals arranged at intervals. The tunable optical device has one or more tuning elements for varying one or more characteristics of the device. The search agent inhibits the return of intermediate, nonconforming search results to the search client, and returns the final, conforming search result to the search client. Furthermore, the prefetching mechanism determines when entry into a different execution phase of an application program occurs, and executes a different prefetching policy based on the application’s program instructions and tag information for that execution phase as well as profile information from previous executions of the application in that execution phase.