TranService: Service and Media Translation System for Small Devices

1. TranService: Service and Media Translation System for Small Devices Graduate School of Media and Governance, Keio University Jun’ichi Yurayurayura@ht.sfc.keio.ac.jp

2. Outline • Background and Goal • System Overview • Implementation • Evaluation • Future works • Conclusion

3. web PC DB PDA Phone news Background • Variation of Services • Web, Database, news ... • Variation of Devices • PC/WS, PDA, WC … → Can not use the services. → Can not get data suitable for the devices. Need to consider the difference of devices and services

4. POWERED BY Goal • Service and media translation system, which consider the difference of devices and services. Cellular Phone Movie Server

5. Device Transparency • Consider the difference among devices • Translation based on device QoS profile PC/WS PDA Web Server Phone

6. Service Transparency • Consider the difference among services • Translation based on service QoS profile web movie Web Client mail

7. QoS Profile • Request contents of QoS(Quality of Service) • Data profile Data type, Data format, Data quality E.g., image/gif (depth: 8bit, size: 180x180) audio/au (frequency: 44.1KHz) • Protocol profile Protocol type, Protocol information E.g., HTTP (Accept: image/gif)

8. Translation Module Part Request C Request S Controller Controller Controller Reply C Reply S Service Module Part Device Module Part Service TS-Proxy Device TS-Proxy • Is proxy server for TranService • Data transcoding • Protocol conversion • Automatic and dynamic transcoding • Loads modules dynamically

9. HTTP Request Context Context Context’ SMTP Data Action Sequence Translation Module Part HTTP SMTP TEXT JPEG GIF MPEG JPEG HTTP HTTP RTSP RTSP Controller Controller Controller POP POP SMTP SMTP Client SMTP Server Service Module Part Device Module Part Convert protocols from HTTP to SMTP

10. Design of QoS Profile • Created by device/service module part • Used by translation module part for deciding transcoding path • XML for sending and receiving • Tree construction in thissystem QOS + DATA | + IMAGE | | + TBMP | | + COLOR=1 | | + DEPTH=0x02 | | + WIDTH=180 | | + HEIGHT=180 | + TEXT | + DEFAULT | + CHARSET=shift-jis + PROTOCOL + HTTP + VERSION=1.1

11. Transcoding Types • Protocol conversion HTTP → POP, SMTP → HTTP • Data transcoding image/jpeg → image/gif image/au → text/plain • Multiple transcoding text/html → audio/au = text/html → text/plain + text/plain → audio/au

12. Implementation • Implementation environment • JDK1.2 / Windows 2000 • Whole system about 5000 lines • Implemented modules (extracts) • Device modules • HTTP device module • Translation modules • HTTP to POP3 protocol translation module • text/html to text/plain data translation module • Service modules • HTTP service module • POP3 service module

13. Application Example (1) • Controlling networked appliances • Switching from video inputs to projectors • Use PDA as Universal Controller Projectors HTML Commands HTTP/TCP/IP Serial TS-Proxy Matrix Switcher Video Inputs PDA

14. Application Example (2) • Browsing support for video streaming • Celluar phone:GIF(8bit-GlayScale, 100x80) PC: JPEG(24bit-Color, 320x240) PC Internet-ready cellular phone

15. Related Works W:WBI, M:KMSF-MCAP, T:TranSend, D:DeleGate, S:tranService

16. 200 150 Whole Time (msec) 100 Transcoding Decision 50 0 0 10 20 30 40 50 Numbers of modules Measurement • 1: Measure entire time A: Receiving data from client, create QoS profile D: Receiving data from server • 2: Measure time taken by transcoding • Transcoding time: 1.2 msec/num • Decision time: 0.7 msec/num Graph 1 Graph 2

17. Future Works • Use distributed modules • Load balancing, fault tolerance • Interoperability to other QoS profiles • MPEG7, CC/PP, HTTP-UserAgent • Categorize service characteristics • State-less or state-full • Number of connections

18. Conclusion • Construct tranService system, which is media transcoding system based on QoS requirements of devices and services • Design • Realize device transparency and service transparency • Implementation • Implemented on JDK1.2 • Evaluation • Measurement • Comparison

20. Application Example (2) • Web mail reader • Users can read web pages by mail-reader • TS-Proxy convert from SMTP to HTTP SMTP/TCP/IP HTTP/TCP/IP TS-Proxy Web Server PDA

21. Example of Module import jp.ac.keio.sfc.ht.tranService.*; public class TextHtmltoTextPlainTranslationModule extends TranslationWorkerModule { public TextHtmltoTextPlainTranslationModule() { // Translation type is Data translation setTranslationType(TranslationServerModule.TRANSLATION_TYPE_DATA); // Input type is "text/html" setInputType(new MimeType("text", "html").toString()); // Output type is "text/plain" setOutputType(new MimeType("text", "plain").toString()); } public void execute() { try { // Receiving context Data data = getNextData(); // Here is a transcoding code ... Omitted ... // Sending context sendData(data); } catch(InterruptedException ie) { ... Ommited ... } } }

22. Context • Data set sent/received between module parts • Content Request from client / reply from server • Content profile A meta-information of content • Device QoS profile QoS profile that refer to device • Service QoS profile QoS profile that refer to service

23. Translation Module Part Request C Request S Controller Controller Controller Reply C Reply S Service Module Part Device Module Part Service TS-Proxy Device System Overview

24. Related Works • Dynamic adaptation • Ability to consider changes of environment dynamically • Extended functionality • Ability to accept for new devices and services • Multiple transcoding • Ability to transcode continuously • Platform independency • Ability to use system on any platform