Issue No. 02 - February (2009 vol. 8)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TMC.2008.104
Shiow-yang Wu , National Dong Hwa University, Hualien
Jungchu Hsu , E-TEN Information Systems Co., Ltd., Taipei
Chieh-Ming Chen , Microelectronics Technology Inc., Hsinchu
Media streaming in mobile environments is becoming more and more important. To avoid service interruptions, proper data management strategies must be taken by all parties. We propose a two-level framework and cooperative techniques for mobile media streaming. Headlight prefetching is for the cooperation of streaming access points to deal with unpredictable client movement and seamless hand-off. For each user, we maintain a virtual fan-shaped prefetching zone along the direction of movement similar to a vehicle headlight. The overlapping area and accumulated virtual illuminance of the headlight zone on a particular cell determine the degree and volume of prefetching on that cell. Dynamic chaining facilitates cooperation among users to maximize cache utilization and streaming benefit. On receiving a request from a client, the streaming access point starts a search for supplying partners before attempting to a remote media server. If a qualified partner is found, the client is chained to the partner and receives subsequent segments without server intervention. The client can itself be a supplying partner for other clients and naturally form a chain of users that are viewing and sharing the same media. Simulation results demonstrate that headlight prefetching and dynamic chaining can significantly decrease streaming disruptions, reduce bandwidth consumption, increase cache utilization and improve service response time.
Mobile Computing, Distributed databases, Indexing methods, Distributed systems, Online Information Services, Mobile Applications
C. Chen, S. Wu and J. Hsu, "Headlight Prefetching and Dynamic Chaining for Cooperative Media Streaming in Mobile Environments," in IEEE Transactions on Mobile Computing, vol. 8, no. , pp. 173-187, 2008.