© 2003 by British Computer Society
A Cost-Based Admission Control Algorithm for Digital Library Multimedia Systems Storing Heterogeneous Objects
1 Department of Computer Science, Virginia Polytechnic Institute and State University, Northern Virginia Center, 7054 Haycock Road, Falls Church, VA 22043, USA Email: irchen@vt.edu, naverma@vt.edu
We present and analyze a cost-based admission control algorithm for handling mixed workloads in modern multimedia systems such as a digital library multimedia system that must provide access services to heterogeneous objects stored in the library. The cost-based scheme considered in the paper is based on the concept of ‘rewards’ and ‘penalties’ associated with requests of various media object types. Instead of admitting object requests until resources are exhausted as a condition for admission control, resources are reserved to requests of different media types dynamically based on the cost-based scheme so that the system is capable of maximizing the total reward received by the system in response to workload changes in the environment. We analyze the maximum queue sizes for admitting discrete media requests to meet the imposed response-time constraints and for improving the total reward received by the system by exploiting leftover resources from servicing continuous media requests. A solution for the total reward obtainable is derived and validated via simulation.