Consider a content distribution network consisting of a set of sources, repositories and clients where the sources and the repositories cooperate with each other for efficient dissemination of dynamic data. In this system, necessary changes are pushed from sources to repositories and from repositories to clients so that they are automatically informed about the changes of interest. Clients and repositories associate coherence requirements with a data item , denoting the maximum permissible deviation of the value of known to them from the value at the source. Given a list of ¡data item, coherence¢ served by each repository and a set of ¡client, data item, coherence¢ requests, we address the following problem: How do we assign clients to the repositories, so that the fidelity, that is, the degree to which client coherence requirements are met, is maximized? In this paper, we first prove that the client assignment problem is NP-Hard. Given the closeness of the client-reposit...
Shetal Shah, Krithi Ramamritham, Chinya V. Ravisha