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

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.

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.

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.

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

Source: Dr. Chu’s Lecture I in the Ubicomp course 2005 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

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

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

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...

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

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

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

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.

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.

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.

Boards Multipurpose: Interacting with electronic chalk. 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.

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

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)

Microkernel Architectural Pattern Infrastructure Application

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)

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

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

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.

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

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

Backup

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.

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…

Blackboard Advantages of BB: Disadvantages 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

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.

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.