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W@P. By: Christopher M. Logan Date: April 19, 2001. What is WAP?. . What is WAP?. W ireless A pplication P rotocol Based on HTTP and XML An open global specification - PowerPoint PPT Presentation
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W@PBy: Christopher M. Logan
Date: April 19, 2001
What is WAP?
<A little understanding of what WAP really is! />
What is WAP?What is WAP?
Wireless Application ProtocolBased on HTTP and XMLAn open global specificationEmpowers mobile users with wireless devices to access
and interact with information and services instantlyBackbone protocol that lest you connect to the Internet
across any digital wireless network and through any wireless device,application, and service provider
What is WAP (cont’d)What is WAP (cont’d)
Global multi-layered protocol that is designed to bring content to thin-client devices
A “thin-client” device can range from low-end, display limited cellular telephones, to full functionality, high-speed laptop computers.
A client is termed “thin” based on any one of the following attributes:
Display and data entry constraintsMemory or CPU processing constraints.
The WAP protocol is designed to address the needs of this full range of client devices
What is WAP [cont’d]What is WAP [cont’d]
Standardized by the W@P Forum
www.wapforum.org
WAP History
<!-- Wireless Beginnings -->
Wireless BeginningsWireless BeginningsDetroit police using crude mobile radios as early as 1921Mobile communication slowly developed through out the ’20s,
’30s and ’40sMid ’40s cellular came to light
Researchers knew that air wave would be filled with voice traffic and interference
Discovered that service area could be divided into small “cells”Radio frequencies could ne reused which increased call capacity
1947 AT&T proposed that the Fedral Communication Commission (FCC) allot a large band of radio frequencies for mobile telephones.
1969 the frequencies were available
Wireless Beginnings (cont’d]
Wireless Beginnings (cont’d]1971 AT&T submitted how a “cellular system” could be
established over the extended radio frequencies to the FCCDelayed until 1977
1978 2000 Bell Telephone customers in Chicago tested the first mobile phones operating on a cellular system.
Analog system called Advanced Mobile Phone Service (AMPS)Still in use today.
1996 Three major digital systems are available.Time Division Multiple Access (TDMA)
AT&T Wireless, and Southwestern BellCode Division Multiple Access (CDMA)
Wireless Beginnings [cont’d]
Wireless Beginnings [cont’d]
SprintPCS, GTE, Air Touch, and Verizon> 1994 FCC opened up the Personal communication Services (PCS)
frequencies to 1900MHz which unlike other services using AMPS, PCS spectrum is all digital
» Voice mail, FAX, paging, and Short Messaging Service (SMS) are now available
» Cell phones can act like modems» Paved the way for a direct connection between the wireless world
and the WWW.Global System for Mobile Communications (GSM)
Pacific Bell and OmnipointThey all process voice signals differently but sounds virtually
identical.
WAP History
<b> How WAP came into being … </b>
WAP HistoryWAP HistoryBefore July 1997 each telecommunication giant was
developing their own protocols and markup languages for wireless Internet access.
Nokia: Narrow Band Sockets (NBS).Using Tagged Text Markup Language (TTML).Aimed at bringing HTML content to the handset.Supported in the Nokia 8010i.
Ericsson: Intelligent Terminal Transfer Protocol (ITTP).Aimed at providing enhanced call control.
WAP History (cont’d]WAP History (cont’d]
Phone.com: Handheld Device Markup Language (HDML)Aimed at providing a “web-like” environment for the development of
network based applications and services.Created WAP.
The diversity threatened to fragment the wireless data access market.
Along with Motorola, they believed that is was in their best interest to create a forum to discuss wireless Internet data access standards.
WAP History (cont’d]WAP History (cont’d]
The W@P Forum was created on July 27, 1994Primary goal is to insure interoperability and growth
of the wireless market.Over 500 members
» Dues: $27,500/yr to join as a full member» Dues: $7,500/yr to join as an associate member.
Wireless Peculiarities
<What WAP is designed for />
Wireless PeculiaritiesWireless Peculiarities
Basically, wireless networks are flaky.Devices can go in and out of range.
When they do come back in they could be on a totally different network.
Small Bandwidth.Technologies boast 40Mbits/sec.
You basically need to be near a powerful antenna to get this data rate» (and a dose of radiation) if you really want it!
Vulnerable to interference, distance and load.All effecting transmission speeds.
WAP Features
<? How WAP Deals with the Peculiarities />
WAP FeaturesWAP Features
WAP is designed for wireless networks.Designed to deal with wireless peculiarities.
Wireless Sessions: wireless devices may go in and out of range.Wireless sessions give the wireless device the opportunity to suspend
an application session on the content server before the device goes out of range.
Content server saves application specific data.When coming back into range the device can resume the wireless
session and continue where it last left off.
Wireless Features [cont’d]Wireless Features [cont’d]
Device Abstraction:WAP has the concept of User Agent Profiles which is a
representation of the client device on the application server.
Allows a wireless application to server a wireless client differently depending on the device being used.
> Some devices might require different content because their displays are small or their input device is limited in some way.
WAP Features [cont’d]WAP Features [cont’d]
Bearer Abstraction:Devices don’t always use the Internet Protocol (IP).WAP provides a way for the underlying protocol to be
abstracted, whether it is IPv4, IPv6, SMS, Bluetooth, or Mobittex.
WAP can suspend sessions over bearers.A device can suspend a session on one bearer and
resume on another.
WAP Features [cont’d]WAP Features [cont’d]
Data/Header Compression:All data and headers are compressed to ensure optimal
bandwidth of wireless bandwidth.
ReliabilityWAP provides reliable transport over any bearer in the same
way Transmission Control Protocol (TCP) does, but with low bandwidth.
Supports Segmentation and Reassembly (SAR) for bearers which do not support it natively.
Why not HTTP/HTML?
<body Why HTTP/HTML wasn’t chosen …/>
Why not HTTP/HTML?Why not HTTP/HTML?
Lost PagesSlow responsesNo “push” abilityBad content
WAP Architecture
<What WAP is made of …/>
WAP ArchitectureWAP Architecture
WAP Stack: Takes into consideration, Low bandwidth, Need for “push”, Unpredictable networks, and many different bearers.
Wireless Session Protocol (WSP)Wireless Transport Protocol (WTP)Wireless Transport Layer Protocol (WTLP)Wireless Datagram Protocol (WDP)
WAP Architecture (cont’d]WAP Architecture (cont’d]
WML Browser: Front end to the stack on the CLIENT
Parses the Wireless Markup Language (MWL) and Wireless Markup Language (WMLS).
Displays formatted text and graphics on the client device.
This is the IE and Netscape of wireless devices.
WAP Architecture (cont’d]WAP Architecture (cont’d]
WAP Gateway: Front end to the stack on the SERVER
Primary goal is to emulate the behavior of a web browser.
It allows the wireless device to communicate over the IP-based web.
Encodes content for the low bandwidth telecom network.
Content can be WML, HTML, or streamed data.
WAP Architecture (cont’d]WAP Architecture (cont’d]
Origin Server: AKA the Content ServerReceived HTTP requests from the WAP Gateway
from the user. Returns content based on the request.
Internet Vs WAPInternet Vs WAP
WAP layersWAP layers
WAP NetworkWAP Network
WAP Example….WAP Example….
Apache Configuration…Apache Configuration…
The End…The End…