1. MWCN`03 Singapore 28 October 2003
Universal Access Service Architecture for Mobile Devices in a Collaborative System
MWCN`03 Singapore 28 October 2003
Sangyoon Oh
Sunghoon Ko
Geoffrey C. Fox
PTLIU for Community Grids Lab.
Indiana University, IN, USA

2. Outline Introduction Idea Collaborative system and messaging system
Design Objects
Architecture
Future work
Conclusion

3. Introduction
Importance of network-ready personal devices in collaborative systems is becoming apparent.
Mobile devices overcome physical constraint
Raise the degree of collaboration
Universal access allows users to access information system regardless of device type and its capability.

4. Idea But integration of disparate devices is difficult
Limitations of computing power (CPU, memory, and display), connectivity (unstable and various network protocols) and developing environment (various OS)
A dedicated middleware architecture that supports universal access, event mapping, user management, and content adaptation

5. Collaborative system
Collaborative Systems supports coordination and cooperation of two or more people who attempt to perform a task or solve a problem together
Sharing states (resource)
Examples: distance education, collaborative computing and building electric communities.
Sharing audio, video, display, text, file

6. Garnet Collaboration System
Garnet system
Uniform XML event (message) based architecture
All data structures defined in XML Schema Garnet XML Object Specification: GXOS
Build on publish/subscribe messaging model
customization to different client character
Support collaborative features : basic interactive features (textchat, whiteboard, etc.), shared resources (shared display, shared export), AV conferences
Grids (web) service interface: future
Grid computing requires the use of software that can divide and farm out pieces of a program to as many as several thousand computers. Grid computing can be thought of as distributed and large-scale cluster computing and as a form of network-distributed parallel processing. It can be confined to the network of computer workstations within a corporation or it can be a public collaboration (in which case it is also sometimes known as a form of peer-to-peer computing).

7. NaradaBrokering NaradaBrokering system
A distributed event service infrastructure developed for a large network of cooperating broker nodes
Supports publish-subscribe model for clients, JMS compliant

8. Design Objects Efficiency Heterogeneity Server side computing
Move computation to Server side
Deliver only vital parts of the message
Minimum computation on user device
Hand Held Message Service Protocol (HHMS)
Byte oriented event message
Contains topic type, application type, event type, and event data
Heterogeneity
Core concern of ubiquitous computing environment
Content adaptation
Transcoding: customize contents for limited capable mobile device
User Profile: GXOS based
Based on the user profile and device type of current machine, this architecture adapts the content of message appropriate to the user device.
Processing large size image cost a lot in computing resources.
Scalability
Additional application  adding processing module
Event based message  do not interrupt each other

9. Architecture Overview
Pure Java: J2ME and J2SE

10. Architecture Personal Server (PDA_Adaptor) Content Adaptor
Connection Manager
Applications

11. Architecture: Personal server and Content Adaptor
Personal server (PDA_Adaptor)
Main component
Manage user state: Create Content Adaptor Module and destroy it
Content adaptor
Responsible for processing adaptation of collaborative event message according to user profile
Each application has a process module in Content Adaptor

12. Architecture: Connection Manager
TCP connection for WLAN device
HTTP Tunneling for Cellular phone
Tomcat Server + Servlet
Client polls to check incoming message
Servlet has a job queue for each client
Provides network interface to

13. Architecture: Applications
Collaboration applications
Shared Display
sharing framebuffer among clients
Customizable picture size and resolution
SVG (Scalable Vector Graphics)
SVG module gets URL of SVG file and process it
Session Textchat
Instant Messenger
Instant messenger transport module connects Jabber open server to deliver a instant message and check presence (eXtensible Messaging and Presence Protocol: XMPP)

14. SVG Demo (Snapshot)

15. Shared Display Demo. (Snapshot)

16. Textchat Demo. (Snapshot)

17. Future Work Integrate with message broker (NaradaBrokering)
Core functionality: NaradaBrokering Agent
Content Adaptation: Web Service

18. Conclusion
Pushing down more computing on the middleware layer and use efficient protocol between a mobile application and the middleware is suitable for many pervasive computing environment
Content Adaptation
Data processing
Event service
NaradaBrokering – HHMS protocols

19. Relate URLs Community Grids Lab GMSME NaradaBroker GXOS
GMSME
grids.ucs.indiana.edu/ptliupages/hhms
NaradaBroker
GXOS