Understand Mobile Technologies
What?
Chao-Hsien Chu, Ph.D.
School of Information Sciences and Technology
The Pennsylvania State University
Understand Mobile Computing
What ?
Where ?
How ?
Why ?
Mobile Technologies – What?
100 mbs
Throughput
10 mbs
Broadband Cellular
1 mbs
3G Cellular
100 kbs
2.5G Cellular
10 kbs
2G Cellular
10 m
100 m
Distance
1 km
10 km
Mobile Technologies – What?
• Cellular / PCS:
- Cell phones
- PDAs
- PC cards
• Location Based Services:
- Network
- Handset
• SIM Cards:
- Personal data
- Stored minutes (prepay)
- Stored value (m-cash)
• Message Technologies:
- Email
- SMS
- IM
• Telematics:
- Private vehicles
- Commercial
• Telemetry
US Carriers
29.4m cust.
cdmaOne
AMPS/CDPD
cdma2000
1XRTT
21.3m
GSM/GPRS
GSM/GPRS
AMPS/TDMA EDGE
SBC (60%)
BellSouth (40%)
19.4m (incl.
TeleCorp)
AMPS/TDMA GSM/GPRS
EDGE
DoCoMo (16%)
14.4m
cdmaOne
8.1m
iDEN
6.5m
GSM/GPRS
cdma2000
1XRTT
Verizon (55%)
Vodafone (45%)
All 1900 mHz
iDEN 2
Looking to be
acquired???
GSM/GPRS
Deutsche
Telekom (100%)
Mobile Computing Standards
2000
GSM
2001
9.6 to 43.2 Kb/sec
CDMA
14.4 – 64 Kb/sec
cdmaOne (95A-95B)
iDEN
9.6 Kb/sec
CDPD
19.2 Kb/sec
ReFLEX
2003
2004
2005
9.6 to 14.4 Kb/sec
TDMA
Mobitex &
DataTAC
2002
115 Kb/sec
(GPRS)
384 Kb/sec
(EDGE)
144 Kb/sec
(cdma2000 1XRTT)
60-70 Kb/sec
384+ Kb/sec
(UMTS)
384 Kb/sec
(cdma2000 EVDV)
???
4.8 to 19.2 Kb/sec
9.6 Kb/sec
2G
64 Kb/sec (NextGen ReFLEX ???)
2.5G
3G
Mobile Protocol Standards
• GSM: Global Systems for Mobile Communications.
• TDMA: Time Division Multiple Access.
• CDMA: Code Division Multiple Access.
• iDEN: Integrated Digital Enhanced Network.
• CDPD:Cellular Digital Packet Data.
• Mobitex & DataTAC: Packed-switch Mobile Data
Network.
• UMTS: Universal Mobile Telecom System.
Bluetooth
• 1994 – Ericsson
• 1998 – Bluetooth SIG
- 2000+ members
• PAN - Personal Area Networking
• 2.4 gHz
• 10 m radius
- No line-of-sight requirement, as with IR
• 128 bit security encryption
• Up to 720 Kb/sec.
• Low cost chip (max $5)
- Can be fitted into anything!
802.11 Standard Series
• Wireless IP networking for home and office
- Limit range: 150 m
• 802.11b: 11 Mb/sec @ 2.4 gHz
- Bluetooth conflicts?
• 802.11a: 54 Mb/sec @ 5 gHz
• 802.11g: 22  54 Mb/sec @ 2.4 gHz
- Newest std; forward compatibility.
• Benefits:
- User mobility: home, office, even public locations!
- Flexibility: P2P, access point (wireless hub), hand-over.
- Cheaper: infrastructure. Old building, fault tracking.
• Issues: significant security problems.
Types of Mobile Applications
• Notification (paging)
• Two-way Messaging
• Interactive Data Exchange (Sales order entry,
status, ticket purpose).
• Email (supports, attachments)
• M-Commerce
• On-line information inquiry.
• Telemetry.
• Location-based services.
• M-Learning.
Mobile Challenges
• Many different kinds of device technologies:
- Internet enabled desktops, PDAs, WAP phones, pagers
- Different devices support multiple kinds of browsers
• Many network protocols with different characteristics:
- Voice, data, messaging support traffic from real-time conversations to
one-way messaging.
- WAP, GSM, CDMA, TDMA, CDPD, AMPS, SMS, TCP/IP, Mobitex,
ReFlex
• Many different kinds of services to be delivered:
- Sales, services, support, marketing, distribution, …
• Many different delivery situations:
- In the office, at a customer site, in the airport, on a plane, on the road,
at home, you named it.
• Industry-standard protocols are not fully emerges yet.
Mobile Challenges
• Unfriendly communication environment:
- Fluctuating coverage conditions caused by weather, buildings,
mountains, devices.
- May have coverage holes
• Narrow bandwidth and low speeds.
• Interoperability Issues.
• Roaming workforces.
• Limitations of current devices and protocol.
• Security.
Limitations of Wireless
 Bandwidth limitations.
 Incomplete service coverage.
 Scarcity of contents
 Lack of an installed user base.
 High customer cost.
 Changing communications standards.
 Security.
Trends in Mobile Devices
• Faster processors
• More memory
• Screens:
- Bigger
- More color depth
- Bitmap addressable
• New user interfaces:
- Keyboard (built-in/attachable)
- Joysticks
• Device convergence:
- Hybrid phone/PDA/Pocket PC
• Cameras / MP3 Player
• Virtual Machines/Browsers
How do Applications run on Devices?
• Native OS
• Virtual Machine Library over Native OS
• Markup in a Browser
VM Application
Content
Application
VM (App)
Browser (App)
Device OS
Device OS
Device OS
Processor
Processor
Processor
Web vs. Mobile Development
Internationalization
B&W or Color
Available
Memory
Application Server
Data Server
Voice
J2ME
PalmCl
WML
BREW
HDML
cHTML
HTML
Screen sizes/
resolutions
Keyboards vs.
Soft Buttons
Messaging
Application
Languages
OS Versions
Browser
versions
Handset
scripting
Language
versions
Developing Services for Multiple Devices
• Custom Development:
- If you control the mobile devices.
- If you have unlimited resources
• Transcoding:
- HTML content scraped and re-marked up
- Not recommended for long term
• XML/XSL:
- Some limitations in what a style sheet can do
- It is also up to your programming skill
• Presentation Server:
- Virtualize presentation definition
Areas Mobile Technologies Help
Area
Problem Solved
Decision Support
Information mobility.
Shorten cycle time; reduce cost.
Performance
Support
Timely and up-to-date information.
Effectiveness.
Efficiency
Access information in the field.
Reduce redundant activities
Utilization
Supplying and capturing information remotely.
Avoid asset downtime, increase productivity
Customer
Satisfaction
Convenient, mobility, flexibility
Advantages to Win Competition
Time
Services
Quality
Cost
Competitive Advantages
 Cost / Price:
- Initial Cost.
- Life Cycle Cost.
 Quality:
- Reliability.
- Features.
- Performance.
 Time:
- Fast Delivery Time.
- On Time Delivery.
- New Systems Development Speed.
 Flexibility:
- Functionality Changes.
- Format Changes
- Interfaces …
Benefits of Mobile Computing
Benefit
Underlying Mechanism
Better decision
making
• More complete, and up-to-date information at moment of decision
making
Shorter response
time and process
cycle time
• Instantly act on new developments triggered by notification and
alerts.
• Initiate execution of subsequent activities from mobile location.
• Faster information dissemination among sales, field service and
customer support staff and the like
• Capture data in electronic format at point of creation.
Remove
inefficiencies and • Simply data exchange between mobile works and back-office
reduce error
systems.
rates
• Eliminate duplicate data entry in disparate applications
Convenience
•
•
•
•
Easy anywhere, anytime access to information and applications.
Manage tasks when away from desk.
Key information readily at hand.
Faster access to electronic stored information.
Benefits of Mobile Computing
Benefit
Underlying Mechanism
Improved
productivity
• Increase first-time success rate.
• Reduce administrative activities.
• Improve resource deployment, scheduling and task
assignment.
• Use down-time more productive.
Increase
customer
satisfaction
•
•
•
•
Increase
customer
retention &
loyalty
• Differentiate product/service with mobile extensions.
• Increase barrier to switch.
Work from up-to-date client related status/issues information.
Faster response to customer requests
Handle everything on the spot.
First time right.
Business Benefits
There are no "wireless" problems,
only business problems.
•
•
•
•
•
•
•
Improving customer relationships
Reducing errors
Increasing productivity
Strengthening communications
Reducing Latencies (faster turnaround)
Quicker and easier access to information
Improving support
Thank You?
Any Question?
Determinants for Wireless Services
Size
Weight Form
Screen Size
Color
User Interface
Screen Characteristics
Antenna
Audio Capabilities
Style
Design
Mobility
Battery Life
Operating Models
Voice Quality
Security
Function Coverage
Area
Roaming
Cell Radius
Efficiency
Privacy
Affordability
Cell
Marketing
Infrastructure
Operating Cost
Management
Operator
Customer
Handset
Service Contract
Roaming Charge
Operating Cost
Accessories
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Limitations of Wireless - Pennsylvania State University