research issues in adapting computing to small devices francis c.m. lau department of computer...
Post on 31-Mar-2015
213 Views
Preview:
TRANSCRIPT
Research Issues in Adapting Research Issues in Adapting Computing to Small DevicesComputing to Small Devices
Francis C.M. Lau
Department of Computer Science
The University of Hong Kong
APPT 2005 • Hong Kong
fcmlau@cs.hku.hk
APPT 05 (27/10/05, HK) 2
Popular ComputingPopular Computing
• 70’s: one computer, many users• 80’s: one computer, one user• 90’s: many (connected) computers,
many users – distributed computing• Now: many computers, one user
• What next? Ubiquitous computing? Grid computing? Service-oriented computing? …– Do we need that many computers?– Do we need a “computer”?
APPT 05 (27/10/05, HK) 3
Windows PanicWindows Panic
• Continue or quit or kill the window or details?
• How would my mother know!?
• The best computing is without the computer
APPT 05 (27/10/05, HK) 4
Imagine …Imagine …
• APPT 2015 (Disneyland, Hong Kong) …
APPT 2015APPT 2015
APPT 05 (27/10/05, HK) 5
My Future HandheldMy Future Handheld
• All in one: phone, PDA, wallet, game console, remote terminal, ad-hoc networking …
• That means a lot of software – big and fat!?
• But what I really want is lean and thin and mean– Lean – simple software which does only what I want
– Thin – that’s all the space in my pocket, or around my neck!
– Mean – affordable
LTMLTM
APPT 05 (27/10/05, HK) 6
LTM ComputingLTM Computing
• The (thin-) client-server paradigm, works but in limited ways
• Too thin: a browser-only device, a remote terminal …
• Future devices are more powerful than just that– But how powerful is
powerful?
APPT 05 (27/10/05, HK) 7Subramanian, 1999
O my god!
Software complexity
APPT 05 (27/10/05, HK) 8
Rich ComputingRich Computing
• My hard disk and VM can be as big as the Internet
• Not just contents, but software come and go on demand
• Pay-per-use subscription model• Browser plug-in’s and Java applets –
not lean enough, and some require just too much resources
• Software in terms of “functionalities”
The Networkis the Computer ™
APPT 05 (27/10/05, HK) 9
The Network Behind Every DeviceThe Network Behind Every Device
• Future digicams– Snap and go
• The network is the memory• The network is the photo album• (The network is NOT the power)
– Context aware
APPT 05 (27/10/05, HK) 10
Edge ComputingEdge Computing
• Person .. device .. middleware (proxies) .. Internet
• The abstract cloud moves with the client – personalized “cuddleware”, nomadic computing
Internetproxies united
client
metropolis
APPT 05 (27/10/05, HK) 11
DEVICEEDGE
GRID
The continuum: WHAT SHOULD BE DONE The continuum: WHAT SHOULD BE DONE WHERE?WHERE?
APPT 05 (27/10/05, HK) 12
A ContinuumA Continuum
• Your device .. other devices (peers) in the vicinity .. server(s) nearby .. the grid– “Neighborhood” is still important
• network bandwidth can’t be infinite; latency will never be 0; network will never be trouble-free
• What should be done where?– The end-device: completely passive (HAS) to c
ompletely active (DIY)
APPT 05 (27/10/05, HK) 13
““Hire a Server”Hire a Server”
• Completely passive (remote terminal)– A waste of bandwidth– Responsiveness and interactivity (esp. for
games)• Does it make sense?
– MP3, camera, PDA, …
• Something must be done locally– Adaptation
APPT 05 (27/10/05, HK) 14
Limits You Can’t BeatLimits You Can’t Beat
• Power?• Screen size: foldable, rollable, we
arable, projectable? Or do without the screen (audible?)– Convenience and privacy; and po
wer consumption– Resolution helps a little bit
• Why I don’t use a PDA (I just ordered an 24” LCD; but I still look at my watch)– Ergonomics is very important– Scrolling is a nuisance (now)– User experience!
APPT 05 (27/10/05, HK) 15
Wearable Wearable ComputersComputers
server
display
APPT 05 (27/10/05, HK) 16
AdaptationAdaptation
• Data– = not code
• Content– A special kind of data– Text, paged, non-text– Pixel level and/or higher
• UI– Higher level, structural, interactive– Buttons, icons, menus, panels and panes … content
• Code
APPT 05 (27/10/05, HK) 17
Componentized SoftwareComponentized Software
• Executable code as puzzle pieces
• Fast start, like contents• Software download
pipelining – first-come-first-execute, the most needed functionalities first
APPT 05 (27/10/05, HK) 18
The Need for Code On DemandThe Need for Code On Demand
• How many functions have you ever used?
A simplified view of Microsoft Word
APPT 05 (27/10/05, HK) 19
Remember UNIX?Remember UNIX?
• Small is beautiful• Make each program do one
thing well• Choose portability over
efficiency• Store data in flat ASCII files• Avoid captive user interfaces• Make every program a filter• …
APPT 05 (27/10/05, HK) 20
UNIX Philosophy AppliedUNIX Philosophy Applied
• Small software components implementing single functionalities
• Bigger functions runtime-composable from small components
• Download on demand, and disposable
• Standard formats and interfaces (eg. XML)
• Shared GUI
APPT 05 (27/10/05, HK) 21
Service-Oriented ComputingService-Oriented Computing
Can Web Services Scale Down?
- for small device apps
APPT 05 (27/10/05, HK) 22
Adapting X to YAdapting X to Y
• Many issues– Psychology– Aesthetics– Readability, convenience, privacy …– Economics
• Context awareness– Because small devices are likely mobile– The user moves around
APPT 05 (27/10/05, HK) 23
Awareness and AdaptationAwareness and Adaptation
• An intelligent supporting architecture
• Aware of the come and go of mobile users
• Choices of functions, depending on situation: the location, the device, the user, …
• Fast reacting nearby proxy• Proxies united, within certain
locality
APPT 05 (27/10/05, HK) 24
Summary 1: Summary 1: BasicBasic Problems (I Problems (I think) Worth Pursuingthink) Worth Pursuing
• Edge computing → “seamless”– New protocols for the edge
• The continuum → the network is the computer– Collaborative models and mechanisms, esp. at the edge
• The global grid → invisible, “PC” disappearing• The device
– Adaptation• On-demand code composition
– The SOC approach?
• Content– HTML
• UI description languages
– New paradigms for user interaction in small devices (input and output)
APPT 05 (27/10/05, HK) 25
Some HKU ProjectsSome HKU Projects
• The Sparkle Project – “code adaptation”• PDF document content adaptation system
– “content adaptation”• HTML adaptation – “UI/content
adaptation”
APPT 05 (27/10/05, HK) 26
SparkleSparkle
• Mobile code on demand– Proxy to device, device to device
• Features– Code On Demand– Context Based Adaptation– Proxy Caching on Code– Code & State Migration– Ontology– Sparkle View & Universal Browser
Application = “facet” composition
APPT 05 (27/10/05, HK) 27
Universal BrowserUniversal Browser
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
Time (ms)
Add Noise AddShadow
FindEdges
FlipHorizontal
FlipVertical
GaussianBlur
OpenImage
Save asJpeg
Sharpen
APPT 05 (27/10/05, HK) 28
PDF Document AdaptationPDF Document Adaptation
APPT 05 (27/10/05, HK) 29
APPT 05 (27/10/05, HK) 30
APPT 05 (27/10/05, HK) 31
APPT 05 (27/10/05, HK) 32
Web Document AdaptationWeb Document Adaptation
APPT 05 (27/10/05, HK) 33
(a) The original content
(b) Only the bottom level is “compressed”
(c) The two lowest levels are “compressed”
APPT 05 (27/10/05, HK) 34
Handling SegmentsHandling Segments
APPT 05 (27/10/05, HK) 35
Summary 2: When I Grow OlderSummary 2: When I Grow Older
• I want a simpler life (others can enjoy all the complexities)– One device, LTM– No computer please; terminal is fine; plug and
play– Single data storage by hire, access anywhere– Single sign-on, single environment (adaptive)
APPT 05 (27/10/05, HK) 36
top related