Platforms and tools for Web
Services and Mobile Applications
Bent Thomsen
Aalborg University
3rd and 4th of June 2004
Welcome to a world
of
Fun
and
Frustrations
Overview
•
•
•
•
•
Overview
Browser based clients
J2ME based clients
.Net CF based Clients
Trends and Future
Mobile computing and wireless
communication just a few years ago
Future Applications
Now I can
really start
‘extreming’
…
Tom downloads an exercise
planning application written in Java.
The application automatically finds and recognizes the various health
monitoring gadgets which Tom is wearing.
While Tom is climbing, the
application monitors the details of
Tom’s condition.
The application automatically develops a near-term fitness plan appropriate for
Tom given his current physical condition.
Shopping in the future
Finding you way around
After one week…
I am going
to teach my
phone my
habits.
Looks cool!
Marie buys a new phone. She is
showing it to her friend Susie.
The device has learnt where Brandi likes to visit and what she does.
Your phone is
peeping
Marie gives names to positions.
Look, it
remembers!
Marie leaves to work, surprised that her phone helped her not to be late.
Definition of Mobile and Wireless
• Mobile
• Mobile, but not wireless
– The ability to be on the move
– Mobile applications are any
applications that can be used
when on the move: PDAs,
laptops, mobile phones
• Wireless
– Stand-alone applications
– Deferred Synchronized
– Dial-up
• Wireless, but not mobile
– Stationary using wireless com
– The transmission of voice or
data over radio waves
– Wireless devices are those
that send or receive data
wirelessly
Image courtesy of “Mobile and Wireless Design Essentials” (Mallick 2003)
Mobile/Wireless Application Options
• Wireless Internet (online only)
– Online access to Web content
– Typically used for consumer applications
– Limited user interface and capabilities
• Smart Client
– Incorporates mobile database technology for persistent data
storage
– Updates to data can be synchronized to enterprise systems
– Allows for offline access to important data
– Works best in ‘occasionally connected’ environment
• Messaging
– Store and forward delivery of data
– Text messaging is very popular, multimedia the next thing
– Can be used on its own, or in addition to other architectures
Variability of the mobile
environment
Mobility
• stationary
• nomadic (pedestrian speed)
• mobile (vehicular speed)
• roaming (mobile across networks)
Connectivity
Mobile Device Capability
• form
factor
• GUI
• multimedia
• real-time multimedia
• connected
• semi-connected
(asymmetric)
• disconnected
M-Commerce
• Digital purchase
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–
–
–
•
•
•
•
•
Ring tones
Pictures
Games
Other applications
Mobile Banking
Information Services
Location based services
Mobile Shopping
Mobile Advertisement
M-Business
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•
•
•
Mobile Office
Field Sales
Field Services
Transportation and Logistics
Which applications are enterprises
interested in launching first?
50%
40%
30%
20%
10%
0%
Wireless
Email
PIM
Internet
access
Respondents saying high interest
Base: 122 Respondents
Gartner Wireless Survey
March 2002
Wireless
CRM/ ERP
Why go mobile?
• The mount Everest Reason (because you
can)
• Business Benefits
– Increased employee productivity
– Faster response time
– Stream lined business processes
– Improved competitive advantage
– Reducing costs
• End-user Benefits
Wireless Environment
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•
•
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Wireless Operators and Service Providers
Device Manufacturers
Hardware vendors
Software infrastructure Providers
Independent Software Vendors
System Integrators
Challenges
• Coverage and
penetration
• Bandwidth
• Latency
• Reliability
• Cost
• Lack of Standards
• Roaming
•
•
•
•
Device Diversity
Infrastructure Choice
Thin vs. Thick clients
Java vs. .Net vs.
C/C++
Device characteristics
•
•
•
•
Size and weight
Memory
Processors type and speed
Screen
– Size and colour
– Indoor/Outdoor
•
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•
OS
Software support
Expansion capabilities
Built-in functionality
Device Characteristics
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Notebook/Laptop
Tablet PC
Handheld PC
High-end SmartPhone
Palm sized PDA
Low-end SmartPhone
Web Phones
SMS capable phones
Two way pagers and SPOT
Devices – Four Types of Footprints
Always On
Always Connected;
No Sync Required
Rich DeviceResident Apps
Local Database
No DeviceResident Apps
No Local
Database
Mobile Extension of
Desktop Desktop-Sync
Offline + Online
Wireless Networks
Satellite
WPAN Illustration
Image courtesy of “Mobile and Wireless Design Essentials” (Mallick 2003)
WPAN Applications
• For business applications, anytime you would
use a cradle for a network connection, a WPAN
can work
– SQL Anywhere Studio can synchronize data wireless
over WPAN networks without modifying the
application!
• In some confined environments, Bluetooth can
be used as a local area network
• As cable replacement for peripherals
• Future uses include many embedded devices
such as sensors, interactive toys, smart badges,
and home automation
WLAN Configurations
• Wireless LAN with
Access Points
Image courtesy of “Mobile and Wireless Design Essentials” (Mallick 2003)
WLAN Applications
• Wi-Fi networks are used throughout the business world
for wireless access to corporate networks
– Warehouse environments for inventory tracking
– Hospitals and clinics for patient care
– Corporate campuses for Internet/Intranet access
• Wi-Fi technology is used in ‘hotspots’ to provide
convenient Internet access
– Check corporate email
– Synchronize smart client applications
– Download latest updates in offline Web applications
WLAN Configurations
Peer to Peer Wireless LAN
Image courtesy of “Mobile and Wireless Design Essentials” (Mallick 2003)
Wide Area Networks
• Main Characteristics:
– Long-range communication (national coverage)
– Data rates from 9.6 kbps to 2 Mbps
– Service agreement required; fee for airtime/data
transfer
– Operate over licensed spectrum (which operators
have to pay to use!)
• WWANs were initially implemented for voice
communication, but data communication is a key focus
with the latest offerings
Circuit Switching vs Packet
Switching
• Circuit Switched
– Need to establish a physical connection between two
communicating parties (i.e. telephone)
– Usage charges based on time of connection
– Connections cannot be shared
– Work well for voice communication; not so well for data
• Packet Switched
–
–
–
–
Dedicated connection not required for communication
Data transferred using packets that contain destination address
Many users can share a single connection
Usage charges based on amount of data transferred
Network issues
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•
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Increased bandwidth
Always-on capability
Lower costs
Enhanced services
Interoperability and roaming
GPRS coverage
Vodafone coverage in the UK
GSM coverage in the US
WWAN Evolution
Image courtesy of “Mobile and Wireless Design Essentials” (Mallick 2003)
3G coverage by 3 in Denmark
WWAN Applications
• WWANs are still primarily used for voice
communications
• Adoption of data services has been strong for
text messaging, and now, multimedia messaging
• Consumer uses include wireless Internet
access, whereas corporate usage is often
focused on smart client synchronization and PIM
and email access
• The widespread deployment of 3G networks has
been hindered by Wi-Fi hotspots
WiFi hotspots in the UK
Network Summary
T yp e o f
N e tw o rk
W ireless
P ersonal
A rea
N etw orks
(W P A N )
W ireless
L ocal A rea
N etw orks
(W L A N )
W ireless
W ide A rea
N etw orks
(W W A N )
S atellite
N etw orks
C o ve ra g e
Are a
personal
operating
space,
typically 10
m eters
In buildings
or cam puses,
typically 100
m eters
C overage
provided on
national basis
from m ultiple
carriers
global
coverage
F u n c tio n
As s o c ia te d
cost
very low
T yp ic a l
T h ro u g h p u t
0.1 – 4 M bps
S ta n d a rd s
low m edium
1 – 54 M bps
802.11a, b, g,
H om eR F ,
H yperL A N /2
E xtension of
LAN
m edium high
8 kbps – 2
M bps
GSM , TDM A,
CDM A, GPRS,
EDGE, W CM A
E xtension of
LAN
very high
2 kbps to 19.2
kbps
W irelessM atrix
cable
replacem ent
technology,
personal
netw orks
E xtension or
alternative to
w ired L A N
IrD A ,
B luetooth,
802.15
Access to Corporate
Infrastructure
Access
Network
WAP
PDA
Clients
GSM
Connections
Dial-up
Connections
Mobile
Network
Firewall
for DMZ
EVO Comms
WAP Gateway
Server
IMAP/SMTP Proxy
HTTP Proxy
Radius
Server
Corporate WAN
(Intranet)
MS Mobile
Exchange
Service
WAP/xHTML Multi-channel
Portal
Information
Service
Service
Existing
Services
Transparent access to Internet
• IP address of MS is allocated from the GPRS operator’s
addressing space
– Static address permanently assigned to MS
– Dynamic address assigned by GGSN at context activation
BTS
BSC
SGSN
GPRS
Core network
GGSN
AP
e.g. APN: web.pro.be
Operator’s ISP network
DNS
Edge router
Internet
Non-transparent access to
intranet or ISP
• IP address of MS allocated from address space of
intranet or ISP
• Subscriber can be authenticated by RADIUS or DHCP
server
BTS
of intranet or ISP
BSC
SGSN
GPRS
Core network
GGSN
AP
e.g. APN:
gprs.telindus.be
Dedicated line
Servers:
RADIUS
DNS
Router
Intranet
GPRS Roaming Network
• GPRS Roaming eXchange (GRX)
– Each GRX acts as a hub of a larger network
Operator F
GPRS Roaming Network
Operator A
Operator B
BG
BG
Operator C
BG
BG
GRX
BG
GRX
BG
GRX
BG
BG
Operator D
BG
Operator E
Mobile and Wireless Application
Architecture
Databases
Legacy Systems
Thin
Client
Fat
Client
External
Applications
Thin Client/Fat Client Scenario
Web Server
Services on Server
Remote Web Pages
Local Code
Mobile Web
Browser
.NET CF & J2ME
Device Operating System
Future Dreams anno 1993
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