The Foundations of Ubiquitous Computing

1. The Foundations of Ubiquitous Computing Author Mark Weiser Xerox PARC (Palo Alto Research Center) Reporter Chun-Feng Liao Mar 25,2005

2. Trilogy of Weiser • Mark Weiser, The Computer for the 21th Century, Scientific American, September 1991. • Mark Weiser, Some computer science issues in ubiquitous computing, Communications of the ACM, 36(7):75-85, July 1993. • Mark Weiser, John S. Brown, The Coming Age of Calm Technology, 1996. Int’l Conference on UbiComp was first hold on 1999. UbiComp 2005: Sep 11-14,2005. Tokyo, Japan.

3. Significance of “The Computer for the 21th Century” • This is not a research paper. • The article is the origin of UbiComp. • Heavily cited by papers in this area. • Several revolutionary concepts of HCI come from Xerox PARC. (ex: Windows, Desktop) PARC = Palo Alto Research Center UbiComp = Ubiquitous Computing, some researchers also call it Pervasive Computing.

4. What can we learn from this article? • Concepts and Definitions of UbiComp. • Visions of UbiComp. • Scenarios of UbiComp(not reported in this seminar). • Challenges of UbiComp. NOTE: Keep in mind that this article was wrote on 1991.

5. How Ubicomp is Related to Our Research • Yellow: Our research area. • Gray: Related research area. : Contained by.. : Supports.. Ontology and Semantic Web Embedded System Distributed Computing HCI / VR Sensing Technologies Context-aware Computing UbiComp Mobile Computing E Home Agent

6. The Evolution Path • Distributed Computing (PC + networks) • Challenges: performance, scalability, server or network failures, open networks, performance, • Mobile computing (Mobile devices + wireless networks) • Challenges: resource-limitation, unpredictable network, power • Ubicomp (Everyday objects + wireless networks) • Challenges: understanding user intention, heterogeneous ubicomp environments, invisible user experience, more .. Source: Dr. Chu’s Lecture I in the Ubicomp course 2005

7. Agenda • Introduction • Key issues of UbiComp • Location and size • Privacy • Requirements of UbiComp • Hardware • Software • Conclusion • Possible Researching Directions

8. The most profound technologies are those that disappear. Mark Weiser, “The Computer for the 21st Century”. Profound: 意義深遠的。

9. Computer that Disappeared • Weiser and his colleagues in PARC think that the idea of a “Personal” computer itself is misplaced. • “Disappearance” is a fundamental consequence of human psychology. • Ex: Writing, electrical motors, silicon-based devices...

10. VR versus EV (Embodied Virtuality) • “Perhaps most diametrically opposed to our vision is the notion of ‘virtual reality’ ”, which attempts to make a world inside the computer. • Embodied Virtuality: the process of drawing computers out of their electronic shells. Virtual World VR: 將現實世界放到虛擬世界中 Real World EV: 將電腦中的數位資訊帶入現實生活 Embodied: 具體化

11. Ubicomp v.s Agents • “Ubicomp is exploring quite different ground from personal digital assistants or autonomous agents” [Weiser93] Invisibility is critical in Ubicomp !! 為什麼都不用花力氣? 黃老 黃老 Object Object I want to move that object Agent Agent(Invisible) Yes sir, I will do it for you 因為我在暗中幫你推… Traditional Agent Ubicomp Agent

12. Research Methods of Ubicomp • Standard experimental Computer Science: • Construct working prototype • Evaluate working prototype in everyday use • Find out real vs. imaginary issues

13. Key Issues of UbiComp • Location and Scale • Location: ubiquitous computers must know where the are in order to provide appropriate services. • Scale: tabs, pads and boards. Note: The Concept of “Location” was extended to “Context” by Brown et, al.(in PARC) in 1994, published in special issue on “Context in Design” in Journal of HCI.

14. Tab • Clip-on computers roughly the size of an employee ID card. • Doors open only to the right badge wearer. • Rooms greet people by name.

15. Pad • Pads are not portable computers • The pad that must be carried from place to place is a failure. • Pads are intended to be “scrap computers” that can be grabbed and used anywhere. • Pads may even be as small and light as actual paper • Many electronic pads around on the desk, just as you spread out papers.

16. Boards • Multipurpose: • In home: video screens and bulletin boards. • In office: bulletin board, white boards or flip charts. • Book case: download texts to a pad or tab. • Interacting with electronic chalk.

17. Requirements of Ubicomp: Invisibility • Cheap, low-power computers • Display • Large display: must be viewable form arm’s length as well as from across a room. • High-speed wireless network • Software systems • Software architecture : Microkernel architectural • Middleware

18. Zero Configurations • In Ubicomp environment, local devices come and go • The context in an environment may change frequently. • New software for new devices may be needed at any time. • Microkernel architecture may offer an solution. (CMU Aura Project and Vrige Univ. at Amsterdam)

19. Infrastructure Application Microkernel Architectural Pattern

20. Software Architectures of Context-aware Computing Blackboard architecture for context-aware computing(Stanford). Blackboard Architectural Pattern (POSA) MVC Architectural Pattern (POSA) Context Widget architecture (Georgia Tech) Microkernel Architectural Pattern (POSA) Microkernel (PARC,CMU-Aura) Service-oriented Architecture (Singapore Univ.,IEEE Computer 2004) Ontology, Semantic Web Agent-orient, Mobile Agent, Multi-agent Pipeline / Filter (POSA)

21. 4 1 3 2 Core Idea of Blackboard Blackboard Expert A Expert B Moderator (又稱Control) Expert C Predefined Heuristic Function (又稱Knowledge Sources)

22. Context Server/Context Widget Architecture “每一個Entity會有一個Context Server” Context Server for Television Context Server for John Voice Context Widget Env Context Widget Vision Context Widget Camera Laser Ranger Speech Recognizer Thermometer

23. Conclusion • This article provides the vision and challenges for UbiComp. • Tabs, pads and boards are just the beginning of UbiComp. • The real power comes from the interaction of all of them. • The hundreds of processors have no “user interface” like mouse or windows, just a pleasant and effective “place” to get things done.

24. Possible Researching Topics • A pattern system for context-aware computing. • Comparing each architectural design and identifying their trade-offs. • Distributed computing issues on context-aware computing • Identifying distributed computing issues and solve with enhanced distributed computing algorithms. • Synchronization • Mutual Exclusions • Leader Election

25. Possible Researching Topics • Cross-cutting concerns of UbiComp • Security, Privacy, Transaction, Synchronization, Service Lookup… • Aspect-oriented middleware for UbiComp. • UbiComp and the Semantic Web • Context representation with RDF. • Home robot

26. Backup

27. Privacy Issues • How to avoid inappropriate use of personal information. • Morris’s Rule • Build computer system to have the same privacy safeguards as the real world, but no more, so ethical conventions will be automatically applied.

28. Scenario • Coffee is ready before the clock alarm. • Privacy configurations, adaptive video data-rate. • Tangible media(newspaper, circle to transmit). • Finding things. • Check traffic in car. • Finding parking lot. • Greeting according to one’s badges. • Virtual office / conference • More…

29. Blackboard • Advantages of BB: • Support for changeability and maintainability. • Reusable knowledge sources. • Support for fault tolerance. • Disadvantages of BB: • Difficulty of testing • Low efficiency • High development effort • No support for parallelism

30. Context Widget • Acquiring a certain type of context information, make this information available in a general manner. • Obtain the context without having to worry about how the context was sensed.

31. Context Server • Gather and manage context about a single entity. • Behave as a proxy to the context for applications. • Support 4 primary context types, also need to support the retrieving of secondary context information.