Transcript Wap

Betty and the GeEks
Present:
Wireless
Communication
What is WAP?
• A set of protocols which allow data
exchange for mobile cellular systems
• The current world standard for the
presentation and delivery of wireless
information
• It is device independent
• It is network independent
Current Constraints of
Wireless Interfaces:
Mobile Devices:
•
Less Bandwidth
•
Less CPU Power
•
High Latency
•
Less Memory and Storage
•
Less Stable Connections
•
Restricted Power Consumption
•
Less Predictable Availability
•
Small / Variable Sized Displays
•
Diverse range of network
standards
•
Variable Input Types
(Keypad, Pen, etc,)
Why Use WAP ?
• Wireless networks and phones
– have specific needs and requirements not
addressed by existing Internet technologies.
• WAP enables any data transport
– TCP/IP, UDP/IP, GUTS (IS-135/6), SMS, or USSD.
• The WAP architecture
– has several modular entities which together form
a fully compliant Internet entity
– all WML content is accessed via HTTP 1.1
requests.
Why Use WAP ? (cont..)
• WAP utilizes standard Internet markup language
technology (XML)
• Optimizing the content and airlink protocols
• The WML UI components map well onto existing
mobile phone user interfaces
– no re-education of the end-users
– leveraging market penetration of mobile devices
• WAP utilizes plain Web HTTP 1.1 servers
– leveraging existing development methodologies
– CGI, ASP, NSAPI, JAVA, Servlets, etc.
The WAP Architecture
Web Server
WAP Gateway
WML
WML Encoder
WMLScript
WSP/WTP
WMLScript
Compiler
HTTP
CGI
Scripts
etc.
WTAI
Protocol Adapters
Etc.
Content
WML Decks
with WML-Script
Client
More Acronyms to learn
•WAE - Wireless Application Environment
•WSP - Wireless Session Protocol
•WTP - Wireless Transaction Protocol
•WTLS - Wireless Transport Layer Security
•WDP - Wireless Datagram Protocol
Comparison between Internet and WAP Models
Internet
Wireless Application Protocol
Wireless Application
Environment (WAE)
HTML
JavaScript
Other Services and
Applications
Session Layer (WSP)
HTTP
Transaction Layer (WTP)
Security Layer (WTLS)
TLS - SSL
Transport Layer (WDP)
TCP/IP
UDP/IP
Bearers:
SMS
USSD
CSD
IS-136
CDMA
CDPD PDC-P
Etc..
WAP Protocols
• WSP (Wireless Session Protocol)
– Provides the application layer of WAP with a
consistent interface for two session services.
• A connection-oriented service that operates
above the transaction layer protocol WTP.
• A connectionless service that operates above
a secure or non-secure datagram service
(WDP).
WAP Protocols
• WTP (Wireless Transaction Protocol)
– Provide efficient request/reply based
transport mechanism suitable for devices
with limited resources over networks with
low to medium bandwidth.
• WTP Push mode allows server to “push” data
to a client without request (e.g. notification
of stock hitting target price)
• WTP/WDP uses less than half the packets
that TCP/IP uses to transfer the same
amount of data.
WAP Protocols
• WTLS
(Wireless Transport Layer Security)
– A security protocol based upon the industrystandard Transport Layer Security (TLS)
protocol, formerly known as Secure Sockets
Layer (SSL). WTLS is intended for use with
the WAP transport protocols and has been
optimized for use over narrow-band
communication channels.
WAP Protocols
• WDP (Wireless Datagram Protocol)
– The Transport layer protocol in the WAP
architecture
– Provides a common interface to the Security,
Session, and Application layers
– Allows these upper layers to function
independently of the underlying wireless
network. This is the key to global
interoperability
WAP Developers
An incomplete list of corporations currently
developing WAP products and/or services:
 AT&T
 Bell Atlantic Mobile
 GTE
 Sprint PCS
 US West
 Nextel
 France Telecom
 Telenor (Norway)
 Bell Mobility (Canada)
 Japan Telecom
 Nokia
 Ericsson
 Motorola
 Qualcomm
 Samsung
 Palm Computing (3Com)
 IBM
 Phone.com (Unwired Planet)
WML
Wireless Markup Language
• Tag-based browsing language:
– Screen management (text, images)
– Data input (text, selection lists, etc.)
– Hyperlinks & navigation support
• XML-based language
• Inherits technology from HTML
WML
Wireless Markup Language
• Card metaphor
– User interactions are split into cards
– Navigation occurs between cards
• Explicit inter-card navigation model
– Hyperlinks
– UI Event handling
– History
• State management and variables
– Reduce network traffic
– Results in better caching
A WML Example
<WML>
<CARD>
<DO TYPE="ACCEPT" LABEL="Next">
<GO URL="#card2"/>
</DO>
Acme Inc.<BR/>Directory
</CARD>
Acme Inc.
Directory
_____________
Next
<CARD NAME="card2">
<DO TYPE="ACCEPT">
<GO URL="?send=$type"/>
</DO>
Services
Services
1>Email
<SELECT KEY="type">
2 Phone
<OPTION VALUE="em">Email</OPTION>
3 Fax
<OPTION VALUE="ph">Phone</OPTION> ____________
<OPTION VALUE="fx">Fax</OPTION>
OK
</SELECT>
</CARD>
</WML>
Wireless Networking
Technologies (PAN/LAN)
• Flarion Technologies
– OFDM (Orthogonal Frequency Division
Multiplexing)
• GSM
– 3G (A third generation mobile technology)
• Bluetooth
Bluetooth
The Bluetooth wireless technology allows
users to make effortless, wireless and
instant connections between various
communication devices, such as mobile
phones, Personal Digital Assistants
(PDA’s), desktop and notebook computers.
It currently provides a 2 Mbps data rate and
a range of 500 ft indoors.
Bluetooth
•
The Bluetooth radio is built into a small
microchip and operates in a globally available
frequency band ensuring communication
compatibility worldwide.
•
Software controls and identity coding built into
each microchip ensure that only those units preset
by their owners can communicate.
•
The Bluetooth wireless technology supports
both point-to-point and point-to-multipoint
connections.
POP QUIZ
1. WAP enables mobile phone users to
retrieve information from the internet
TRUE 
FALSE
POP QUIZ
2. WML and WMLScript are based on
HTML and Javascript.
TRUE 
FALSE
POP QUIZ
3. Which of the following is not a layer
protocol in WAP ?
A. WDP
B. WTP
C. HTTP 
D. WSP
POP QUIZ
4. WAP will not provide an interface to
voice-mail or prepaid systems.
TRUE
FALSE 
POP QUIZ
5. What does WAP stand for?
A. Wired American People
B. Wireless Appliance Programming
C. Wacky Amish Pandas
D. Wireless Application Protocol 
Questions ?
Comments ?
Snide Remarks ?