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IT 284 Unit 4 Seminar
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WAP Model
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Wireless WAP Network
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A Wireless “Replacement” for Current Web Standards
IP(UDP) WDP
TCP WTL
HTTP-Session
SSL
HTML
JavaScript
WSP
WTLS
WML
WMLScript
The Wired WEB
WAP
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WAP application
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WAP Architecture
• In a real WAP solution, the main components include:
• WAP Device
• Bearer
• WAP Gateway
• Content
• Content Server
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WAP Architecture (contd)….
Web Server
Content
CGIScripts
etc.
WM
L D
ecks
wit
h W
ML
-Scr
ipt
WAP Gateway
WML Encoder
WMLScriptCompiler
Protocol Adapters
Client
WML
WML-Script
WTAI
Etc.
HTTPWSP/WTP
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WAP Architecture (contd)…
.
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WAP Architecture (contd)…• WAE - holds the tools that wireless Internet
content developers use. • WSP - determines whether a session between the
device and the network will be connection-oriented or connectionless.
• WTP - acts like a traffic cop, keeping the data flowing in a logical and smooth manner. It also determines how to classify each transaction request:
– Reliable two way (WTP/C)– Reliable one way (WTP/T) – Unreliable one way (WTP/D)
• WTLS - provides many of the same security features found in the Transport Layer Security (TLS) part of TCP/IP.
• WDP - makes it easy to adapt the transport layer to a variety of bearers because all that needs to change is the information maintained at this level.
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WAP Components (contd)…
• WAP Gateway– Encoder: converts WML to binarized WML– Adaptor: provides additional information
through HTTP header• Translate HTTP requests to WSP.
• Convert between SSL and WTLS
• Convert transport protocols (TCP and WDP)
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WAP Components (contd)…
• WML (Wireless Markup Language)– An XML-based markup language that describes how WAP content
is presented on a wireless terminal
• Differs from HTML in the following – WML was specifically designed for wireless terminals with a target
screen that is only a few lines long and about an inch wide.– WML is case sensitive, and all tags and attributes should be in lowercase.– Unlike HTML, WML is unforgiving of incorrectly nested tags.– WML doesn't assume that a keyboard or a mouse is available for user
input.
• Based on these differences, WML provides a smaller, telephony-aware set of tags that make it more appropriate than HTML for handheld wireless terminals.
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WAP Content
• WAP content (WML and WMLScript) is converted into a compact binary form for transmission over the air
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WAP Microbrowser
• The WAP microbrowser software within the mobile device interprets the byte code and displays the interactive WAP content
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Some WAP applications
• Location-based services– Real-time traffic reporting
– Event/restaurant recommendation
– Highly customized ads
– Instant messaging-type “buddy” location
• Enterprise solutions – Email access
– Database access
– A “global intranet”– Information updates “pushed” to
WAP devices
Financial services– Banking– Bill-paying– Stock trading– Funds transfers
Travel services– Schedules and rescheduling– Reservations