2 Reading list Still working on it Indoor localization
Embedding computing into (everyday) objects Interactions Ubiquitous
healthcare Security and privacy protection Skip systems and sensor
networks & shorten the overview
4 Course Wiki Add your WhoIsWho Add paper review (next week)
Select papers
Slide 5
5 History 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. M. Satyanarayanan. "Fundamental
Challenges in Mobile Computing." Fifteenth ACM Symposium on
Principles of Distributed Computing, May 1996. M. Satyanarayanan.
"Pervasive Computing: Vision and Challenges." IEEE Personal
Communications, August, 2001.
Slide 6
6 M. Weiser. The Computer for the 21th Century", Scientific
American, September 1991.
Slide 7
7 Two Key Points Ubiquitous computing = computing integrated
with physical environment Computing being everywhere, yet people do
not take notice of them Computing becoming disappearing and
invisible Location and scale are important. Adapt their behavior
intelligently without AI: call forwarding, follow-me display,
reminder, good substitute for computer vision, etc. Scale suitable
to different tasks (heterogeneous systems and networks)
Slide 8
8 Examples of Disappearing Technologies Writing Electric Motors
They are everywhere (embedding & hidden into physical objects),
yet invisible. When a technology matures, they disappear! Maturity
= cheap, small, widely applicable, good usability,
Slide 9
9 Why Good Technology Is Invisible? Good technology stays out
of the way of task Like a good pencil stays out of the way of the
writing Bad technology draws attention to itself: Like a broken, or
skipping, or dull pencil Computers are mostly not invisible They
dominate interaction with them. Ubicomp is about making computers
invisible.
Slide 10
10 Ubicomp vs. Virtual Reality Should we live in virtual
computing world? Or should computing come out and live in our
physical world? VR simulates physical world & puts people
inside virtual computing world. Ubicomp is about bringing computing
to peoples physical world. Computing Embed into everyday objects
(intelligent objects) Integrate with social activities (social
computing)
Slide 11
11 Ubicomp vs. Multimedia Multimedia grabs user attention for
entertainment purpose. Ubicomp reduces user distraction, allowing
people to focus on tasks. Alternative output display on periphery
of user attention: (ambient display)
Slide 12
12 Ubicomp Components Computing embedded and enhancing physical
objects Ubicomp = sensors + processors + networking sensors + SW
systems & middleware Example: Intelligent Transportation System
(foreview mirror)
Slide 13
13 PARC Ubicomp Work (1991) Focus on devices that transmit
& display information. Device scale targets different tasks.
Consider three sizes: tabs, pads, boards.
Slide 14
14 Tabs Inch-scale Ubicomp devices Post-It notes Carried around
by a person Hundreds in a room Credit cards, ID cards Remote
controllers Badges Tags / Labels (RFID) Locating system (tags as
library catalogs) Animate static physical objects (active calendar,
active map)
Slide 15
15 Pads Foot-scale Ubicomp devices A sheet of paper / tablet PC
Tens in a room Like scrap papers that can be grabbed and used
anywhere, no unique ID. Like windows in Apple Macintosh, but can
spread them out on a real desk.
Slide 16
16 Boards Yard-scale Ubicomp device One in a room White board
with e-chalk Shared white board with remote participants Video
screen Electronic Bookcases
Slide 17
17 Hardware Challenges (1991) High resolution flat panel
display (cheap) High speed processor High capability storage High
bandwidth wireless Network Lower power consumption How well do
todays HW technologies meet these challenges?
Slide 18
18 Software Challenges (1991) Dynamic configuration of HW/SW in
ubicomp environments (dynamic systems) Application migration across
heterogeneous ubicomp environments Transparent linking of wired and
wireless networks (heterogeneous networks) How well do todays SW
technologies meet these challenges?
Slide 19
19 Sal Scenario Proactively brew coffee informed by alarm clock
Electronic Trails of neighbor coming and going Automatic recording
pen Paper display (e-ink) Email locates garbage door opener (RFID
& object reminder) Window tells weather (ambient display)
Intelligent car navigation (location-based services) Share
location, tabs & pads with Joe (CSCW) Gesture to project
blinking tab to projector (multi-model UI) Memory augmentation on
meeting with Mary (lifelog)
Slide 20
20 Privacy Hundreds and thousands of invisible computers
sensing and watching people Ubiquitous camera recording
Slide 21
21 Is Weiser really Wise? What is the problem that he wants to
solve? What is his proposed solution? Any problems with the
proposed solution? Invisibility & Intelligence vs. privacy RFID
in supermarket Hidden security camera Invisible vs. transparent
Diagnose problems
Slide 22
22 M. Weiser. Some computer science issues in ubiquitous
computing.Communications of the ACM, 36(7):75-85, July 1993.
Slide 23
23 Key Point Based on their PARC experiments with tabs, pads,
and boards, this paper tries to define some ubicomp challenges and
where ubicomp is going.
Slide 24
24 Ubicomp as Experimental CS Construct working prototype
Evaluate working prototype in everyday use Find out real vs.
imaginary issues
Slide 25
25 Hardware Issues Power consumption: impossible to change
batteries to many ubicomp devices frequently. Balance of HW/SW
feature: display, network, processing, memory, storage capability,
multitasking, etc. Ease of expansion & modification
(integration vs. modular design)
28 Application Issues Applications are of course the whole
point of ubiquitous computing. Locating people (active badges)
Automated call forwarding Tracking down people for meeting Watching
general activity in a building (feel in touch with surrounding
environments) Shared drawing in virtual meeting Scalability to 5000
peoples (multicast for bandwidth efficiency)
Slide 29
29 Location Privacy Centralized location database as one
possible solution, but not scalable, vulnerable to single point of
attack, one break-in reveals all. Move toward more distributed
approach.
Slide 30
30 Computational Method Issue Due to unpredictable network to
ubicomp devices, (file) caching can be used to improve
performance.
Slide 31
31 Discussion Open .
Slide 32
32 M. Weiser, J. S. Brown. "The Coming Age of Calm Technology."
1996.
Slide 33
33 Key Points Why the need for calm technology? Computers
everywhere Pay attention in order to use them Information
overloading Solution for design of ubicomp technology Place
information in periphery of user attention But allow fast &
easy moving to center
Slide 34
34
Slide 35
35 Computing Trends These trends are results of computing
getting smaller, faster, and cheaper. Mainframe Era: many people
sharing a computer. PC Era: one computer per person Internet Era:
(interconnecting PCs) Ubicomp Era: many computers (everyday
objects) sharing one person interconnecting everyday objects
Slide 36
36 Calm Technology Calm and uncalm technology differs how to
engage our attention. Divide our attention into two parts:
periphery and center. Periphery is informing without overburdening
While driving a car, center = roads and radio, periphery = engine
noise Calm technology can move easily & quickly between
periphery and center. Calm requires good design affordance (visual
clue to the function of an object)
Slide 37
37 Three Signs of Calm Technology Move easily from center to
periphery and back Enhance periphery reach (more details in the
periphery) Video vs. voice conferencing Good information
visualization
Slide 38
38 Examples of Calm Technology Inner Office Windows Extend
periphery to what are going on the hallway E.g., notice lunch
gathering, meeting, but not distracting to work In comparison to
open cubicles with low partitions Force too much to the center
E.g., noises in the hallway can become distracting to work
Slide 39
39 Dangling String Represent bits flowing over a wire through
motion and sound. The output is (beautifully?) integrated with our
physical environment.
Slide 40
40 Discussion Is Ubicomp defined by the devices or user
experience? Imbed vs. Embed? Are inner office window and dangling
string really calm and relaxing? Does Calm give more or less
information? This is related to ambient display research. UI People
know more about this research area?
Slide 41
41 M. Satyanarayanan. "Fundamental Challenges in Mobile
Computing", Fifteenth ACM Symposium on Principles of Distributed
Computing, May 1996.
Slide 42
42 Key Points What are fundamental challenges in mobile
computing (What is so special about mobile computing)?
Resource-limited mobile devices Mobility is hazardous Unpredictable
wireless networks Finite power source Adaptation is key to
mobility.
Slide 43
43 Evolution from Distributed Systems to Mobile Computing What
are fundamental differences between Distributed Systems and Mobile
Computing? Distributed systems = Applications running over
Computers Connected Over Network Mobile systems = Applications
running over mobile devices connected over wireless networks Mobile
devices constraints: resource-limited, finite power source,
easy-to-lose (weak security) Wireless network constraints:
unpredictability bandwidth and frequent disconnections
Slide 44
44 Adaptation is Key to Mobility Adapt applications to
continuously changing computing environment (due to mobility):
Power, network bandwidth / availability,
Slide 45
45 Adaptation Strategies Need resource management at the system
layer to allocate resources to different applications. Need
application level semantics, e.g., frame-rate, resolution, etc. The
best approach is to have both application and system supports.
Slide 46
46 Extended Client Server Model Traditional (thin) client (fat)
server model in distributed computing needed adjustments to address
unpredictable network, finite power, and performance. Extended
client-server model (called smart client model) places some server
functionalities to client.
Slide 47
47 Coda & Odyssey Coda supports application-transparent
adaptation. It is distributed file system (FS). It can cache/hoard
some parts of FS on client. It can support disconnected operations
from FS cache. Odyssey supports application-aware adaptation. Adapt
application quality/fidelity (e.g., video framework, resolution)
based on dynamic network condition, power saving, and processing
loads.
Slide 48
48 Research Topics for Exploration Caching metrics (what to
cache/hoard?) Caching coherence (Semantic callbacks and validators)
Algorithms for resource revocation Agility ( ) vs. stability
(Global) Resource estimation from local observations
Slide 49
49 M. Satyanarayanan. Pervasive Computing: Vision and
Challenges, IEEE Personal Communications, August, 2001.
Slide 50
50 Key Points What are fundamental challenges in
pervasive/ubicomp computing (What is so special about pervasive
computing)? Effective use of smart spaces Invisibility Localized
Scalability Masking Uneven Conditioning We will hear a
distinguished talk from author directly.
http://www.cs.uiuc.edu/news/dls/distlectpst.htmlhttp://www.cs.uiuc.edu/news/dls/distlectpst.html
Slide 51
51 Discussion What exactly is proactivity? How does it differ
from adaptation? Is Ubicomp still about old technical issues..
Integrating different technologies, devices and services. Resource
discovery protocol Optimization (different parameters such as
power) Adaptation (with environments)