CEG 436/636: Mobile Computing

Prabhaker Mateti

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What is Mobile Computing?

• There are not going to be any defs.• Essential characteristcs?• Reconsider this topic at the end of the term

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Mobile devices

performance

Pager• receive only• tiny displays• simple text

messages

Mobile phones• voice, data• simple graphical displays

PDA• graphical displays• character recognition• simplified WWW

Smartphone• tiny keyboard• simple versions

of standard applications

Laptop/Notebook• fully functional• standard applications

Sensors,embeddedcontrollers

No clear separation between device types possible (e.g. smart phones, embedded PCs, …)

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Mobile Devices Everywhere

• 2011: There are 5.3 billion mobile subscribers– == 77% of the world population.– Growth is led by China and India.

• 2009: Half a billion accessed mobile Internet.• 2008: Cell Phones Key to Teens’ Social Lives,

47% Can Text with Eyes Closed.

CEG436: Mobile Computing

Google Nexus One Cost (Jan 2010)

5Introductory price US$529 unlocked; US$179 with 2 year contract

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The Growth of Mobile Devices

• Bunch of numbers … next few slides

• Worth watching: – http://www.youtube.com/watch?v=0aUQLIPdtg8

• 3min 11 secs • by Sybase Inc • Sep 9, 2010

7

Mobile statistics snapshots (09/2002 / 12/2004 / 04/2006 / Q4/2007

• Total Global Mobile Users• 869M / 1.52G / 2G / 3.3G• Total Analogue Users 71M / 34M / 1M• Total US Mobile users 145M / 140M • Total Global GSM users 680M / 1.25G 1.5G /

2.7G• Total Global CDMA Users 127M / 202M • Total TDMA users 84M / 120M • Total European users 283M / 343M • Total African users 18.5M / 53M / 83M• Total 3G users 130M / 130M • Total South African users 13.2M / 19M / 30M• European Prepaid Penetration 63% • European Mobile Penetration 70.2% • Global Phone Shipments 2001 393M / 1G 2008 • Global Phone Sales 2Q02 96.7M

sources: www.cellular.co.za/stats/stats-main.htmwww.gsmworld.com

• #1 Mobile Country China (139M / 300M) • #1 GSM Country China (99M / 282M / 483M) • #1 SMS Country Philipines • #1 Handset Vendor 2Q02 Nokia (37.2%) • #1 Network In Africa Vodacom (6.6M / 11M) • #1 Network In Asia Unicom (153M)• #1 Network In Japan DoCoMo • #1 Network In Europe T-Mobile (22M / 28M) • #1 In Infrastructure Ericsson • SMS Sent Globally 1Q 60T / 135G / 235G / 650

G• SMS sent in UK 6/02 1.3T / 2.1G• SMS sent Germany 1Q02 5.7T • GSM Countries on Air 171 / 210 / 220• GSM Association members 574 / 839• Total Cost of 3G Licenses in Europe 110T€ • SMS/month/user 36

CEG436: Mobile Computing

The figures vary a lot depending on the statistic, creator of the statistic etc.!

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Worldwide Smartphone Landscape TBDSource: AdMob traffic

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Worldwide Smartphone Traffic TrendsSource: AdMob traffic, Sept. ‘08

0%

20%

40%

60%

80%

May-08 Jun-08 Jul-08 Aug-08 Sep-08

Symbian Windows Mobile RIM Palm iPhone

WW Smartphone OS Share

WW Smartphone Share of Total Mobile Traffic

15%

20%

25%

30%

May-08 Jun-08 Jul-08 Aug-08 Sep-08

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1010

US Smartphone Landscape Source: AdMob traffic

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1111

US Smartphone Traffic TrendsSource: AdMob traffic, Sept. ‘08

0%

10%

20%

30%

40%

May-08 Jun-08 Jul-08 Aug-08 Sep-08

RIM Windows Mobile Palm iPhone Symbian

US Smartphone OS Share

US Smartphone Share of Total Mobile Traffic

15%

20%

25%

30%

May-08 Jun-08 Jul-08 Aug-08 Sep-08

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Nielsen Mobile Insights, Mar 2011

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World Telecommunication in 2010Key Global Telecom Indicators for the World Telecommunication Service Sector in 2010(all figures are estimates)

  GlobalDvlopednations

Dvlpingnations

AfricaArabStates

Asia & Pacific

CIS Europe Americas

Mobile cellular subscriptions(millions)

5,282 1,436 3,846 333 282 2,649 364 741 880

Per 100 people 76.2% 116.1% 67.6% 41.4% 79.4% 67.8% 131.5% 120.0% 94.1%

Fixed telephone lines(millions) 

1,197 506 691 13 33 549 74 249 262

Per 100 people 17.3% 40.9% 12.1% 1.6% 9.4% 14.0% 26.6% 40.3% 28.1%

Mobile broadband subscriptions(millions)

940 631 309 29 34 278 72 286 226

Per 100 people 13.6% 51.1% 5.4% 3.6% 9.7% 7.1% 25.9% 46.3% 24.2%

Fixed broadband subscriptions(millions)

555 304 251 1 8 223 24 148 145

per 100 people 8.0% 24.6% 4.4% 0.2% 2.3% 5.7% 8.7% 23.9% 15.5%

Source: International Telecommunication Union (October 2010)   via: mobiThinking

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Smartphone OS market shareWorldwide smartphone operating system (OS) market share, according to Gartner

 

Smartphone OS market share and compound annual growth rate (CAGR), according to IDC

OS2009market share

2010market share

2011market share

2015market Share

 2011market share

2015market Share

2011-2015CAGR

Android 3.9% 22.7% 38.5% 48.8%   39.5% 45.4% 23.8%BlackBerry 19.9% 16.0% 13.4% 11.1%   14.9% 13.7% 17.1%iOS 14.4% 15.7% 19.4% 17.2%   15.7% 15.3% 18.8%

Symbian 46.9% 37.6% 19.2% 0.1%   20.9% 0.2% -65.0%

Windows Phone/Mobile

8.7% 4.2% 5.6% 19.5%   5.5% 20.9% 67.1%

Others 6.1% 3.8% 3.9% 3.3%   3.5% 4.6% 28.0%

Total smartphones sold

172 million

297 million

468 million

631 million

 450 million

N/A 19.6%

Source: Gartner (April 2011) Source: IDC (March 2011)

via:mobiThinking

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Applications I

• We can imagine just about every application to have a version implemented on the mobile platform– computing (both CPU and RAM) capacity– storage expectations– graphics/ display expectations– ui expectations

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Applications II• Vehicles

– transmission of news, road condition, weather, music via DAB/DVB-T– personal communication using GSM/UMTS/LTE– position via GPS– local ad-hoc network with vehicles close-by to prevent accidents, guidance

system, redundancy – vehicle data (e.g., from busses, high-speed trains) can be transmitted in

advance for maintenance

• Emergencies– early transmission of patient data to the hospital, current status, first

diagnosis– replacement of a fixed infrastructure in case of earthquakes, hurricanes,

fire etc.– crisis, war, ...

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Typical application: road traffic

ad ho

cUMTS, WLAN,DAB, DVB, GSM, cdma2000, TETRA, ...

Personal Travel Assistant,PDA, Laptop, GSM, UMTS, WLAN, Bluetooth, ...

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Mobile and wireless services – Always Best Connected

UMTS2 Mbit/s

UMTS, GSM384 kbit/s

LAN100 Mbit/s,WLAN54 Mbit/s

UMTS, GSM115 kbit/s

GSM 115 kbit/s,WLAN 11 Mbit/s

GSM/GPRS 53 kbit/sBluetooth 500 kbit/s

GSM/EDGE 384 kbit/s,DSL/WLAN 3 Mbit/s

DSL/ WLAN3 Mbit/s

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Applications III• Traveling salesmen

– direct access to customer files stored in a central location– consistent databases for all agents– mobile office

• Replacement of fixed networks– remote sensors, e.g., weather, earth activities– flexibility for trade shows– LANs in historic buildings

• Entertainment, education, ...– outdoor Internet access – intelligent travel guide with up-to-date

location dependent information– ad-hoc networks for

multi user games

HistoryInfo

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Location dependent services• Location aware services

– what services, e.g., printer, fax, phone, server etc. exist in the local environment

• Follow-on services– automatic call-forwarding, transmission of the actual workspace to the

current location• Information services

– “push”: e.g., current special offers in the supermarket– “pull”: e.g., where is the Black Forrest Cheese Cake?

• Support services– caches, intermediate results, state information etc. “follow” the mobile

device through the fixed network• Privacy

– who should gain knowledge about the location

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Effects of device portability• Power consumption

– limited computing power, low quality displays, small disks due to limited battery capacity

– CPU: power consumption ~ CV2f• C: internal capacity, reduced by integration• V: supply voltage, can be reduced to a certain limit• f: clock frequency, can be reduced temporally

• Loss of data– higher probability, has to be included in advance into the design (e.g., defects,

theft)• Limited user interfaces

– compromise between size of fingers and portability– integration of character/voice recognition, abstract symbols

• Limited memory (always in relation to e.g. PCs)– limited usage of mass memories with moving parts– flash-memory or ? as alternative

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Wireless networks in comparison to fixed networks

• Higher loss-rates due to interference– emissions of, e.g., engines, lightning

• Restrictive regulations of frequencies– frequencies have to be coordinated, useful frequencies are almost all occupied

• Lower transmission rates– local some Mbit/s, regional currently, e.g., 53kbit/s with GSM/GPRS or about

150 kbit/s using EDGE – soon Mbit/s with LTE• Higher delays, higher jitter

– connection setup time with GSM in the second range, several hundred milliseconds for other wireless systems – soon in ms range with LTE

• Lower security, simpler active attacking– radio interface accessible for everyone, base station can be simulated, thus

attracting calls from mobile phones• Always shared medium

– secure access mechanisms important

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Areas of research in mobile communication

• Wireless Communication– transmission quality (bandwidth, error rate, delay)– modulation, coding, interference– media access, regulations– ...

• Mobility– location dependent services– location transparency– quality of service support (delay, jitter, security)– ...

• Portability– power consumption– limited computing power, sizes of display, ...– usability– ...

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Simple reference model used here

Application

Transport

Network

Data Link

Physical

Medium

Data Link

Physical

Application

Transport

Network

Data Link

Physical

Data Link

Physical

Network Network

Radio

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Influence of mobile communication to the layer model

Application layer

Transport layer

Network layer

Data link layer

Physical layer

service location new/adaptive applicationsmultimediacongestion/flow controlquality of serviceaddressing, routingdevice locationhand-overauthenticationmedia access/controlmultiplexingencryptionmodulationinterferenceattenuationfrequency

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Overlay Networks - the global goal

regional

metropolitan area

campus-based

in-house

verticalhandover

horizontalhandover

integration of heterogeneous fixed andmobile networks with varyingtransmission characteristics

CEG 436 Course Content

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Prerequisites/Expectations• CEG 402 is officially listed as a prerequisite.• Ideally, also CEG 433 Operating Systems.

– Processes and Threads– File Systems

• Fluency in – Java is expected.– Objective C is not expected.

• Linux experience: at least CEG 233• Android related Java issues will be discussed.• Eclipse IDE for Android will be introduced.• Would be great: own a spare Android phone• Objective C will be introduced.• Lab facilities available, but better to have your own personal computer.

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CEG 436 Grading Weights% wt

Midterm on-line but no surfing 30Final on-line but no surfing 40Lab L1: Case Study In Android 05Lab L2: Case Study In iOS 05Lab L3: Extend an App Your choice: Android/iOS 10Lab L4: Extend an App Your choice: Android/iOS 10

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CEG 436 Course Content1 Course overview, prerequisites;

Android Development-1: Java, Eclipse, ADT, Hello-World; iOS Development

2 Mobile Sys Characteristics; Wireless/Cellular Technologies: 802.11, Bluetooth, CDMA, GSM, GPRS, UMTS, 2G, 3G, 4G

3 Android Development-2: OS refresher, Services, Widgets, Live WP, sensors, case studies

4 Android Internals, iOS Internals 5 Mobile IP: addressing, agents, ad hoc routing 6 Mobile TCP 6 Midterm

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CEG 436 Course Content7 Mobile Computing issues: Life cycle of

processes, almost no swap space, battery conservation; Middleware; Location,

8 Android Devlopment-3: After market firmware development

9 Security and Privacy: SMS attacks, Android Injector

a Mobile-, Distributed-, Cloud-, Ubiquitous-, Pervasive-, ..., Computing

b Final

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CEG 636 Course Content

• All of CEG 436• One additional project or term paper

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Course Websites• www.cs.wright.edu/~pmateti/Courses/436/Top/ WSU CEG

436/636: Mobile Computing; Weekly Schedule, Syllabus, Discussion, Old Exams, ReadingList, Links, Lab Facilities

• developer.android.com/ Android Developer• developer.apple.com/devcenter/ios/ iOS Dev Center • www.sigmobile.org/ International ACM community of researchers

and practitioners who: Perform research in the theory and practice of all areas related to the mobility of systems, users, data, and computing; Expand the evolution of portable computers and wireless networks; Support the convergence of mobility, computing, and information organization; and Improve access, services, management, and applications for mobile computing and communications.

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Books to Read

• “Everyware: The Dawning Age of Ubiquitous Computing”

• Adam Greenfield• Paperback: 272 pages• Publisher: New Riders

Publishing; March 2006• ISBN-10: 0321384016• http://www.youtube.co

m/watch?v=_PKNbueOF5U

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Books to Read

• “Where the Action Is: The Foundations of Embodied Interaction”

• Paul Dourish• Paperback: 245 pages• Publisher: The MIT Press;

New edition edition (August 20, 2004)

• Language: English• ISBN-10: 0262541785• ISBN-13: 978-0262541787

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Books to Read

• Digital Ground: Architecture, Pervasive Computing, and Environmental Knowing

• Malcolm McCullough• Paperback: 290 pages• Publisher: The MIT Press;

(September 23, 2005)• ISBN-10: 9780262633277• Review

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Recommended Text Book

• “Wireless Internet and Mobile Computing: Interoperability and Performance”

• Yu-Kwong Ricky Kwok, Vincent K.N. Lau

• August 2007• Publisher: Wiley, John &

Sons, Incorporated• ISBN: 0471679682

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Recommended Text Book

• “Computer Networks”• Andrew S. Tanenbaum,

David J. Wetherall• 960 pp, 2011, 5/E • Prentice Hall ISBN-10:

0132126958• Slides etc:

http://authors.phptr.com/tanenbaumcn4/

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Text Book

• “Mobile Communications”• Jochen Schiller• Paperback: 492 pages• Addison Wesley; 2 edition

(September 2003)• ISBN-10: 9780321123817

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CEG 436 Order of Lectures

• Because CEG 436 is a 10-week term course skipped for now …

• refreshers on– Operating Systems– TCP/IP Networking– Cellular Telephony

• “Definitions”– Mobile Devices/Smart Phone– What is Android?