Presentation on theme: "Proxy Server Systems for Wireless Mobile Web Service 2001.11.29."— Presentation transcript:
Proxy Server Systems for Wireless Mobile Web Service 2001.11.29
Outline Introduction Related Works Problem Statement Wireless Proxy Server Deployment Single Distributed Discussion and Ideals
Introduction The characteristics of wireless networks Unfixed and lower bandwidth Higher transmission error rate Different MH hardware type How to provide proper services and qualities for each mobile user is important.
Related works J. F. Bartlett, W4 – the Wireless World Wide Web, Workshop on Mobile Computing Systems and Applications, Dec. 1994, pp. 176-178. Designed for PDA-based wireless browser. Maintained a proxy to parse a HTML documents into multiple screens. The proxy sends the preformatted screens to client using a new protocol.
Related works S. Gessler and A. Kotulla, PDAs as Mobile WWW Browsers, Electronic Proc. Second World Wide Web Conference 94: Mosaic and the Web, Oct.1994. The HTML documents was parsed by client. The client communicates with the proxy also using a new protocol. Images won t be transferred until the client request them.
Related works T. B. Fleming, S. F. Midkiff, and N.J. Davis, Improving the Performance of the World Wide Web over Wireless Networks, GLOBECOM 97. Designed a new protocol, named MHSP, to replace the HTTP used between AP and MH. Prefetching Image reduction
Related works Common points Maintaining a dedicated machine to be a wireless proxy Most of them did not support mobility very well Single proxy v.s Distributed proxy
Problem Statement Single proxy architecture The proxy may become a bottleneck Distributed proxy architecture The handoff between proxy servers Cached data Distilled data Client s information …
Distributed Proxy Server System Distilled data Handoff ?
Proxy Server Architecture Information Networking, 2001. Proceedings. 15th International Conference on, 2001 Figure.2, Page: 750
Proxy Handoff Procedure
Proxy Handoff Procedure (cont.)
Message Format Handoff request message Distilled data request message Distilled data message
Discussion Proxy deployment area Too large: degrading to single proxy scenario The capability of MH should be more simple or complicated? How to satisfy all type of service? Not only WWW …