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Transcript of Platforms and tools for Web Services and Mobile Applications Bent Thomsen Aalborg University 3rd and...
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
Tom downloads an exercise planning application written in Java.
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.
The application automatically finds and recognizes the various health monitoring gadgets which Tom is wearing.
Now I can really start‘extreming’
…
Shopping in the future
Finding you way around
Marie buys a new phone. She is showing it to her friend Susie.
Marie gives names to positions. Marie leaves to work, surprised that her phone helped her not to be late.
The device has learnt where Brandi likes to visit and what she does.
Look, it remembers!
I am going to teach my phone my
habits.
Your phone is peeping
Looks cool!
After one week…
Definition of Mobile and Wireless
• Mobile– 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– The transmission of voice or
data over radio waves
– Wireless devices are those that send or receive data wirelessly
• Mobile, but not wireless– Stand-alone applications
– Deferred Synchronized
– Dial-up
• Wireless, but not mobile– Stationary using wireless com
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
Connectivity• connected• semi-connected (asymmetric)• disconnected
Mobile Device Capability• form factor• GUI• multimedia• real-time multimedia
Mobility• stationary• nomadic (pedestrian speed)• mobile (vehicular speed)• roaming (mobile across networks)
M-Commerce
• Digital purchase– Ring tones– Pictures– Games– Other applications
• Mobile Banking• Information Services• Location based services• Mobile Shopping• Mobile Advertisement
M-Business
• Mobile Office
• Field Sales
• Field Services
• Transportation and Logistics
Which applications are enterprises interested in launching first?
0%
10%
20%
30%
40%
50%
WirelessEmail
PIM Internetaccess
WirelessCRM/ ERP
Respondents saying high interest
Base: 122 RespondentsGartner Wireless SurveyMarch 2002
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
• 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
• OS• Software support• Expansion capabilities• Built-in functionality
Device Characteristics
• 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
No Device-Resident Apps
No Local Database
Mobile Extension of Desktop Desktop-Sync
Rich Device-Resident AppsLocal Database
Always On Always Connected; No Sync Required
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
Image courtesy of “Mobile and Wireless Design Essentials” (Mallick 2003)
Peer to Peer Wireless LAN
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
• 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 SummaryType of Network
Coverage Area
Function Associated cost
Typical Throughput
Standards
Wireless Personal Area Networks (WPAN)
personal operating space, typically 10 meters
cable replacement technology, personal networks
very low 0.1 – 4 Mbps IrDA, Bluetooth, 802.15
Wireless Local Area Networks (WLAN)
In buildings or campuses, typically 100 meters
Extension or alternative to wired LAN
low - medium
1 – 54 Mbps 802.11a, b, g, HomeRF, HyperLAN/2
Wireless Wide Area Networks (WWAN)
Coverage provided on national basis from multiple carriers
Extension of LAN
medium - high
8 kbps – 2 Mbps
GSM, TDMA, CDMA, GPRS, EDGE, WCMA
Satellite Networks
global coverage
Extension of LAN
very high 2 kbps to 19.2 kbps
WirelessMatrix
AccessAccessNetworkNetwork MobileMobile
NetworkNetwork
WAP GatewayIMAP/SMTP Proxy
HTTP Proxy
MS MobileExchange
Service
WAP/xHTMLPortal
Service
Multi-channelInformation
Service
ExistingServices
EVO CommsServer
Corporate WAN Corporate WAN (Intranet)(Intranet)
Dial-upConnections
GSM Connections
GPRS Connections
RadiusServer
Firewallfor DMZ
Access to Corporate Infrastructure
WAPPDAClients
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 SGSNGPRS
Core network
GGSN
AP
DNS Edge routerInternet
Operator’s ISP network
e.g. APN: web.pro.be
BSC
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 of intranet or ISP
BTS BSC SGSNGPRS
Core network
GGSN
AP
Router
IntranetServers:RADIUSDNS
Dedicated line
e.g. APN: gprs.telindus.be
GPRS Roaming Network• GPRS Roaming eXchange (GRX)
– Each GRX acts as a hub of a larger network
Operator A
Operator B
Operator C
BG
BG
BG
GRX GRX
GRX
BG
BG BG
BG BG
BG
Operator D
Operator F
Operator E
GPRS Roaming Network
Mobile and Wireless Application Architecture
ExternalExternalApplicationsApplications
Legacy SystemsLegacy Systems
DatabasesDatabases
Thin Thin ClientClient
Fat Fat ClientClient
Thin Client/Fat Client Scenario
Local Code
Remote Web Pages
Web ServerWeb Server
Mobile Web Browser
Mobile Web Browser
.NET CF & J2ME.NET CF & J2ME
Services on ServerServices on Server
Device Operating SystemDevice Operating System
Future Dreams anno 1993