Efficient and Transparent Dynamic Content Updates for 课件.ppt

Current methods of web browsing were designed for the desktop, it’s time to update those for the mobile environment Take out and move the solution diagram to here and animate a change of the pages Take out Efficient and Transparent Dynamic Content Updates for Mobile Clients Trevor Armstrong, Olivier Trescases, Cristiana Amza, Eyal de Lara University of Toronto, Canada 精品文档 Typical Mobile Browsing Scenario 精品文档 Mobile Browsing Problems Current web browsing is poll based Inconvenient, requires user’s attention Browser caches ineffective for rapidly changing dynamic content Wastes battery and money 精品文档 Key Observation Two main types of content changes: Irrelevant Pertinent More irrelevant than pertinent changes Pertinent vs irrelevant content depends on user 精品文档 精品文档 精品文档 Our Approach Allow user to distinguish pertinent from irrelevant Download page only when pertinent information changes Reduce wireless communication Reduce battery consumption 精品文档 How It Works 精品文档 Edge Proxy Monitors state of all web sites in profile Batches cache updates in a single transfer Prefetches all items in a new request 精品文档 Client Wrapper around Pocket Internet Explorer Select areas of interest within a web page Select thresholds of change for numerical values Client profile Used by the edge proxy when updating cache Stored as tree structure 精品文档 Client Profile Example 精品文档 Cache Updates Polling Mobile proxy explicitly requests cache updates Push Based Mobile proxy listens on a specific port for incoming updates Hybrid SMS Edge proxy sends a SMS message to client when updates are available Includes update batch size 精品文档 Poll Based Updates 精品文档 Push Based Updates 精品文档 Hybrid SMS Updates Message Structure WiFi or GPRS 精品文档 Experiment Keep track of four dynamic content web sites Weather () Currency () Stock Values () Online Auction (www.ebay.ca) Evaluation Criteria Data transfers to and from mobile device Energy consumption 精品文档 Real World Traces Three hour traces, played back for