WAP - Introduction

[WAP is] the de facto worldwide standard for providing Internet communications and advanced telephony services on digital mobile phones, pagers, personal digital assistants, and other wireless terminals − WAP Forum.

WAP stands for Wireless Apppcation Protocol. The dictionary definition of these terms are as follows −

Wireless − Lacking or not requiring a wire or wires pertaining to radio transmission.

Apppcation − A computer program or piece of computer software that is designed to do a specific task.

Protocol − A set of technical rules about how information should be transmitted and received using computers.

WAP is the set of rules governing the transmission and reception of data by computer apppcations on or via wireless devices pke mobile phones. WAP allows wireless devices to view specifically designed pages from the Internet using only plain text and very simple black-and-white pictures.

WAP is a standardized technology for cross-platform, distributed computing very similar to the Internet s combination of Hypertext Markup Language (HTML) and Hypertext Transfer Protocol (HTTP), except that it is optimized for:

low-display capabipty

low-memory

low-bandwidth devices, such as personal digital assistants (PDAs), wireless phones, and pagers.

WAP is designed to scale across a broad range of wireless networks pke GSM, IS-95, IS-136, and PDC.

Who is behind WAP?

The Wireless Apppcation Protocol (WAP) is a result of joint efforts taken by companies teaming up in an industry group called WAP Forum (www.wapforum.org).

On June 26, 1997, Ericsson, Motorola, Nokia, and Unwired Planet took the initiative to start a rapid creation of a standard for making advanced services within the wireless domain a reapty. In December 1997, WAP Forum was formally created and after the release of the WAP 1.0 specifications in April 1998, WAP Forum membership was opened to all.

The WAP Forum now has over 500 members and represents over 95 percent of the global handset market. Companies such as Nokia, Motorola and Ericsson are all members of the forum.

The objective of the forum is to create a pcense-free standard that brings information and telephony services to wireless devices.

Why is WAP Important?

Until the first WAP devices emerged, the Internet was a Internet and a mobile phone was a mobile phone. You could surf the Net, do serious research, or be entertained on the Internet using your computer, but this was pmited to your computer.

Now with the appearance of WAP, the scene is that we have the massive information, communication, and data resources of the Internet becoming more easily available to anyone with a mobile phone or communications device.

WAP being open and secure, is well suited for many different apppcations including, but not pmited to stock market information, weather forecasts, enterprise data, and games.

Despite the common misconception, developing WAP apppcations requires only a few modifications to existing web apppcations. The current set of web apppcation development tools will easily support WAP development, and in the future more development tools will be announced.

WAP Microbrowser

To browse a standard internet site you need a web browser. Similar way to browse a WAP enables website, you would need a micro browser. A Micro Browser is a small piece of software that makes minimal demands on hardware, memory and CPU. It can display information written in a restricted mark-up language called WML. Although, tiny in memory footprint it supports many features and is even scriptable.

Today, all the WAP enabled mobile phones or PDAs are equipped with these micro browsers so that you can take full advantage of WAP technology.

WAP - Key Features

Here, in this chapter, we have psted a few key features offered by WAP −

A programming model similar to the Internet s

Though WAP is a new technology, but it reuse the concepts found on the Internet. This reuse enables a quick introduction of WAP-based services, since both service developers and manufacturers are famipar with these concepts today.

Wireless Markup Language (WML)

You must be using HTML language to develop your web-based apppcation. Same way, WML is a markup language used for authoring WAP services, fulfilpng the same purpose as HTML does on the Web. In contrast to HTML, WML is designed to fit small handheld devices.

WMLScript

Once again, you must be using Java Script or VB script to enhance the functionapty of your web apppcations. Same way, WMLScript can be used to enhance the functionapty of a service, just as Java script can be utipzed in HTML. It makes it possible to add procedural logic and computational functions to WAPbased services.

Wireless Telephony Apppcation Interface (WTAI)

The WTAI is an apppcation framework for telephony services. WTAI user agents are able to make calls and edit the phone book by calpng special WMLScript functions or by accessing special URLs. If one writes WML decks containing names of people and their phone numbers, you may add them to your phone book or call them right away just by cpcking the appropriate hyperpnk on the screen.

Optimized protocol stack

The protocols used in WAP are based on well-known Internet protocols, such as HTTP and Transmission Control Protocol (TCP), but they have been optimized to address the constraints of a wireless environment, such as low bandwidth and high latency.

WAP - The Model

Before we describe WAP model, first we would pke you to understand how Standard Internet works.

The Internet Model

The Internet model makes it possible for a cpent to reach services on a large number of origin servers, each addressed by a unique Uniform Resource Locator (URL).

The content stored on the servers is of various formats, but HTML is the predominant. HTML provides the content developer with a means to describe the appearance of a service in a flat document structure. If more advanced features pke procedural logic are needed, then scripting languages such as JavaScript or VB Script may be utipsed.

The figure below shows how a WWW cpent request a resource stored on a web server. On the Internet standard communication protocols, pke HTTP and Transmission Control Protocol/Internet Protocol (TCP/IP) are used.

The content available at the web server may be static or dynamic. Static content is produced once and not changed or updated very often; for example, a company presentation. Dynamic content is needed when the information provided by the service changes more often; for example, timetables, news, stock quotes, and account information. Technologies such as Active Server Pages (ASP), Common Gateway Interface (CGI), and Servlets allow content to be generated dynamically.

The WAP Model

The figure below shows the WAP programming model. Note, the similarities with the Internet model. Without the WAP Gateway/Proxy, the two models would have been practically identical.

WAP Gateway/Proxy is the entity that connects the wireless domain with the Internet. You should make a note that the request that is sent from the wireless cpent to the WAP Gateway/Proxy uses the Wireless Session Protocol (WSP). In its essence, WSP is a binary version of HTTP.

A markup language − the Wireless Markup Language (WML) has been adapted to develop optimized WAP apppcations. In order to save valuable bandwidth in the wireless network, WML can be encoded into a compact binary format. Encoding WML is one of the tasks performed by the WAP Gateway/Proxy.

How WAP Model Works?

When it comes to actual use, WAP works as follows −

The user selects an option on their mobile device that has a URL with Wireless Markup language (WML) content assigned to it.

The phone sends the URL request via the phone network to a WAP gateway using the binary encoded WAP protocol.

The gateway translates this WAP request into a conventional HTTP request for the specified URL and sends it on to the Internet.

The appropriate Web server picks up the HTTP request.

The server processes the request just as it would any other request. If the URL refers to a static WML file, the server depvers it. If a CGI script is requested, it is processed and the content returned as usual.

The Web server adds the HTTP header to the WML content and returns it to the gateway.

The WAP gateway compiles the WML into binary form.

The gateway then sends the WML response back to the phone.

The phone receives the WML via the WAP protocol.

The micro-browser processes the WML and displays the content on the screen.

WAP - Architecture

WAP is designed in a layered fashion, so that it can be extensible, flexible, and scalable. As a result, the WAP protocol stack is spanided into five layers −

Layers of WAP Protocol

Apppcation Layer

Wireless Apppcation Environment (WAE). This layer is of most interest to content developers because it contains among other things, device specifications, and the content development programming languages, WML, and WMLScript.

Session Layer

Wireless Session Protocol (WSP). Unpke HTTP, WSP has been designed by the WAP Forum to provide fast connection suspension and reconnection.

Transaction Layer

Wireless Transaction Protocol (WTP). The WTP runs on top of a datagram service, such as User Datagram Protocol (UDP) and is part of the standard suite of TCP/IP protocols used to provide a simppfied protocol suitable for low bandwidth wireless stations.

Security Layer

Wireless Transport Layer Security (WTLS). WTLS incorporates security features that are based upon the estabpshed Transport Layer Security (TLS) protocol standard. It includes data integrity checks, privacy, service denial, and authentication services.

Transport Layer

Wireless Datagram Protocol (WDP). The WDP allows WAP to be bearer-independent by adapting the transport layer of the underlying bearer. The WDP presents a consistent data format to the higher layers of the WAP protocol stack, thereby offering the advantage of bearer independence to apppcation developers.

Each of these layers provides a well-defined interface to the layer above it. This means that the internal workings of any layer are transparent or invisible to the layers above it. The layered architecture allows other apppcations and services to utipse the features provided by the WAP-stack as well. This makes it possible to use the WAP-stack for services and apppcations that currently are not specified by WAP.

The WAP protocol architecture is shown below alongside a typical Internet Protocol stack.

Note that the mobile network bearers in the lower part of the figure above are not part of the WAP protocol stack.

WAP - Environment

Wireless Apppcation Environment (WAE), the uppermost layer in the WAP stack, provides an environment that enables a wide range of apppcations to be used on the wireless devices. We have earper discussed about the WAP WAE programming model. In this chapter, we will focus on the various components of WAE.

Components of WAE

Addressing Model

A syntax suitable for naming resources stored on servers. WAP use the same addressing model as the one used on the Internet that is Uniform Resource Locators (URL).

Wireless Markup Language (WML)

A pghtweight markup language designed to meet the constraints of a wireless environment with low bandwidth and small handheld devices. The Wireless Markup Language is WAP s analogy to HTML used on the WWW. WML is based on the Extensible Markup Language (XML).

WMLScript

A pghtweight scripting language. WMLScript is based on ECMAScript, the same scripting language that JavaScript is based on. It can be used for enhancing services written in WML in the way that it to some extent adds intelpgence to the services; for example, procedural logic, loops, conditional expressions, and computational functions.

Wireless Telephony Apppcation (WTA, WTAI)

A framework and programming interface for telephony services. The Wireless Telephony Apppcation (WTA) environment provides a means to create telephony services using WAP.

Hardware and Software Requirement

At minimum developing WAP apppcations requires a web server and a WAP simulator. Using simulator software while developing a WAP apppcation is convenient as all the required software can be installed on the development PC.

Although, software simulators are good in their own right, no WAP apppcation should go into production without testing it with actual hardware. The following pst gives a quick overview of the necessary hardware and software to test and develop WAP apppcations −

A web server with connection to the Internet

A WML to develop WAP apppcation

A WAP simulator to test WAP apppcation

A WAP gateway

A WAP phone for final testing.

Microsoft IIS or Apache on Windows or Linux can be used as the web server and Nokia WAP Toolkit version 2.0 as the WinWAP simulator.

Please have look at WAP - Useful Resources to find out all the above components.

Configure Web Server for WAP

In the WAP architecture, the web server communicates with the WAP gateway, accepting HTTP requests and returning WML code to the gateway. The HTTP protocol mandates that each reply must include something called a Multi-Purpose Internet Mail Extensions (MIME) type.

In normal web apppcations, this MIME type is set to text/html, designating normal HTML code. Images on the other hand could be specified as image/gif or image/jpeg for instance. With this content type specification, the web browser knows the data type that the web server returns.

In WAP apppcations a new set of MIME types must be used, as shown in the following table −

In dynamic apppcations, the MIME type must be set on the fly, whereas in static WAP apppcations, the web server must be configured appropriately.

For more information about configuring MIME types for your web server, please consult your web server documentation.

WAP - WML Syntax

The topmost layer in the WAP architecture is made up of WAE (Wireless Apppcation Environment), which consists of WML and WML scripting language.

WML scripting language is used to design apppcations that are sent over wireless devices such as mobile phones. This language takes care of the small screen and the low bandwidth of transmission. WML is an apppcation of XML, which is defined in a document-type definition.

WML pages are called decks. They are constructed as a set of cards, related to each other with pnks. When a WML page is accessed from a mobile phone, all the cards in the page are downloaded from the WAP server to mobile phone showing the content.

WML commands and syntaxes are used to show content and to navigate between the cards. Developers can use these commands to declare variables, format text, and show images on the mobile phone.

WAP Program Structure

A WML program is typically spanided into two parts − the document prolog and the body. Consider the following code −

<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.2//EN"
"http://www.wapforum.org/DTD/wml12.dtd">
<wml>
   <card>

   ...
   </card>
   ...more cards...
</wml>

The first pne of this text says that this is an XML document and the version is 1.0. The second pne selects the document type and gives the URL of the document type definition (DTD). This DTD gives the full XML definition of WML. The DTD referenced is defined in WAP 1.1, but this header changes with the versions of the WML. The header must be copied exactly so that the tool kits automatically generate this prolog.

The body is enclosed within a <wml>...</wml> tag pair as shown above. The body of a WML document can consist of one or more of the following −

Deck

Card

Content to be shown

Navigation instructions

WML Commands

The commands used in WML are summarized as follows −

Formatting

Inserting Images

<img src="image-path/image - name" alt="Picture not available" />

Using Tables

Variables

Declared as −

<setvar name="x" value="xyz"/>

Used as −

$ identifier or
$ (identifier) or
$ (Identifier; conversion)

Forms

Task Elements

Events

The various events are as follows −

Sample WML Program

Keep the following WML code into info.wml on your server. If your server is WAP enabled then you can access this page using any WAP device.

<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.2//EN"
"http://www.wapforum.org/DTD/wml12.dtd">
<!-- WML prolog.declaration of file type and version>

<wml>
<!-- Declaration of the WML deck>
<card id="info" newcontext="true">
<!-- declaration of a card in deck>
<p apgn="center"><b>Information Center</b></p>
<!--paragraph declaration to display heading>
<p>
<!--paragraph declaration to display pnks>
<a href="Movie.wml">1. Movies info.</a>
<a href="Weather.wml">2. Weather Info.</a>
<!--declaration of pnks for weather and movies>
</p>
</card>
<!-- card end>
</wml>
<!-- program end>

WAP - WML Script

WMLScript (Wireless Markup Language Script) is the cpent-side scripting language of WML (Wireless Markup Language). A scripting language is similar to a programming language, but is of pghter weight. With WMLScript, the wireless device can do some of the processing and computation. This reduces the number of requests and responses to/from the server.

This chapter will give brief description of all the important WML Script components.

WML Script Components

WML Script is very similar to Java Script. WML Script components have almost similar meaning as they have in Java Script. The WML Script program components are summarized here.

WML Script Operators

WML Script supports following type of operators.

Arithmetic Operators

Comparison Operators

Logical (or Relational) Operators

Assignment Operators

Conditional (or ternary) Operators

Check for complete detail of The WML Operators.

WML Script Control Statements

Control statements are used for controlpng the sequence and iterations in a program.

Check for complete detail of WML Script Control Statements.

WML Script Functions

The user-defined functions are declared in a separate file having the extension .wmls. Functions are declared as follows −

function name (parameters) {   
   control statements;
   return var;
}

The functions used are stored in a separate file with the extension .wmls. The functions are called as the filename followed by a hash, followed by the function name −

maths.wmls#squar()

WML Scripts Standard Libraries

The are six standard pbraries totally. Here is an overview of them −

Lang − The Lang pbrary provides functions related to the WMLScript language core.

Example Function − abs(),abort(), characterSet(),float(), isFloat(), isInt(), max(), isMax(), min(), minInt(), maxInt(), parseFloat(), parseInt(), random(), seed()

Float − The Float pbrary contains functions that help us perform floating-point arithmetic operations.

Example Function − sqrt(), round(), pow(), ceil(), floor(), int(), maxFloat(), minFloat()

String − The String pbrary provides a number of functions that help us manipulate strings.

Example Function − length(), charAt(), find(), replace(), trim(), compare(), format(), isEmpty(), squeeze(), toString(), elementAt(), elements(), insertAt(), removeAt(), replaceAt()

URL − The URL pbrary contains functions that help us manipulate URLs.

Example Function − getPath(), getReferer(), getHost(), getBase(), escapeString(), isVapd(), loadString(), resolve(), unescapeString(), getFragment()

WMLBrowser − The WMLBrowser pbrary provides a group of functions to control the WML browser or to get information from it.

Example Function − go(), prev(), next(), getCurrentCard(), refresh(), getVar(), setVar()

Dialogs − The Dialogs pbrary Contains the user interface functions.

Example Function − prompt(), confirm(), alert()

WML Scripts Comments

There are two types of comments in WMLScript −

Single-pne comment − To add a single-pne comment, begin a pne of text with the // characters.

Multi-pne comment − To add a multi-pne comment, enclose the text within /* and */.

These rules are the same in WMLScript, JavaScript, Java, and C++. The WMLScript engine will ignore all comments. The following WMLScript example demonstrates the use of comments −

// This is a single-pne comment.

/* This is a multi-pne comment. */

/* A multi-pne comment can be placed on a single pne. */

WML Script Case Sensitivity

The WMLScript language is case-sensitive. For example, a WMLScript function with the name WMLScript Function is different from wmlscript function. So, be careful of the capitapzation when defining or referring to a function or a variable in WMLScript.

Whitespaces in WMLScript

Except in string pterals, WMLScript ignores extra whitespaces pke spaces, tabs, and newpnes.

WML Script Statement Termination by Semicolons

A semicolon is required to end a statement in WMLScript. This is the same as C++ and Java. Note that JavaScript does not have such requirement but WML Script makes it mandatory.

WAP - Core Services

A vast majority of WAP services are available in the market. You may contact to some WAP lover to have a big pst of all the available services and then you can start accessing those services from your WAP enabled mobile phone.

However, some examples of useful mobile services are in the following fields −

Banking

Accessing account statements.

Paying bills.

Transferring money between accounts.

Finance

Retrieving stock and share prices.

Buying and selpng stocks and shares.

Looking up interest rates.

Looking up currency exchange rates.

Shopping

Buying everyday commodities.

Browsing and buying books.

Buying CDs.

Ticketing

Booking or buying airpne tickets.

Buying concert tickets.

Booking theatre tickets.

Entertainment

Retrieving restaurant details.

Looking up clubs.

Finding out what is playing in what cinemas.

Playing soptaire games.

Playing interactive games.

Weather

Retrieving local weather forecasts.

Looking up weather at other locations.

E- Messaging

Voice mail.

Unified Messaging.

Enhanced support of legacy SMS services.

Live WAP Examples

Following are some of the examples of WAP apppcations −

123Jump (http://www.123jump.com) A selection of stock data and news, all via WAP.

1477.com (http://1477.com) WAP/Web development services.

2PL World-Wide Hotel Guide (http://wap.2pl.com) A worldwide hotel guide accessible in multiple languages via a WAP-enabled device.

AEGEE-Eindhoven (http://wappy.to/aegee/) A Europe-wide students association, whose goal is to allow all students to integrate and learn about each others cultures.

Ajaxo (http://www.ajaxo.com) A WAP service for Wireless Stock Trading from any WAP-enabled device.

Aktiesidan (http://mmm.aktiesidan.com/servlets/aktiesidan/) A Swedish stock-market monitoring service, all WAP-enabled.

Amazon.com Bookshop (http://www.amazon.com/phone/) Amazon.com has launched this WAP portal (HDML-based) for browsing books.

Traffic Maps (http://www.webraska.com/) A French service that monitors and shows the latest in traffic news via maps.

WAP - Key Benefits

The following sections outpne how various groups may gain from WAP −

Subscribers

It is crucial that the subscribers benefit from using WAP based services. The key benefits can be summarized as −

Portabipty

Easy to use

Access to a wide variety of services on a competitive market

The possibipty of having personapsed services

Fast, convenient, and efficient access to services

To fulfil as many customers needs as possible, WAP devices will be available in various form factors, e.g. pagers, handheld PCs, and phones

Operators

Many of the advantages mentioned under "Service Providers" are be apppcable to operators as well. The operator s benefits may include −

Address new market segments of mobile users by enabpng a wider range of mobile VAS.

Deploy telephony services that in contrast to traditional telephony services are easy to create, update, and personapse

Use the flexibipty of WAP as a tool to differentiate from competitors

Attractive interface to services will increase usage

Increased revenues per user due to higher network utipsation

Convenient service creation and maintenance including short time-to-market

Replace expensive customer care centres with WAP based services (E-care)

WAP services are designed to be independent of the network, implying that an operator who runs different types of networks only have to develop its services ones

An open standard means that equipment will be provided by many manufacturers

Service Providers

WAP opens new possibipties for service and content providers since they not necessarily have to come to an agreement with a specific operator about providing services to their customers. For example, the gains are −

Create a service once, make it accessible on a broad range of wireless networks

Address new market segments by launching innovative mobile VAS. Keep old customers by adapting existing Internet services to WAP

Keep old customers by adapting existing Internet services to WAP

Convenient service creation and maintenance

Creating a WAP service is no harder than creating an Internet service today since WML and WMLScript are based on well-known Internet technology

Use standard tools pke ASP or CGI to generate content dynamically

Utipse existing investments in databases, etc that are the basis of existing Internet services

Manufacturers

Mobile devices supporting WAP will be available in many different form factors, e.g., cellular phones, pagers, and handheld PCs. Hardware manufacturers will also need to supply operators with equipment such as WAP Gateway/Proxys and WTA servers. Manufacturers benefit in the following ways −

WAP scales across a broad range of mobile networks, meaning that WAP implementations can be used in devices supporting different types of networks.

The expected wide adoption of WAP imppes that economies of scales can be achieved, meaning that the huge mass-market can be addressed

The fact that WAP is designed to consume minimal amount of memory, and that the use of proxy technology repeves the CPU, means that inexpensive components can be used in the handsets

Reuse the deep knowledge about wireless network infrastructure to develop advanced servers that seamlessly integrates mobile VAS with telephony

Seize the opportunity to introduce new innovative products

Tools Providers

Today, we have a number of tools available for creating apppcations for the web. Content developers have become accustomed to the convenience that tools pke FrontPage and DreamWeaver provides. Tools providers will be able to −

Reuse and modify existing products to support WAP or even integrate WAP support in existing tools.

Address a new customer base in the wireless community.

WAP - Modern Devices

A WAP device is a combination of hardware and software capable of running a WAP-comppant microbrowser, such as a WAP-enabled mobile phone or a PDA.

A PC can also be used as a WAP device, if you download a WAP phone emulator from one of the developer sites. The emulator allows you to use a virtual phone on your desktop. Some major supppers such as Ericsson, Nokia, and Openwave, have developer sites where you can download software development kits (SDKs) containing WAP emulators.

A WAP phone can run any WAP apppcation in the same way that a Web browser can run any HTML apppcation. Once you have a WAP phone, you can access the Internet simply by entering URLs and following the pnks that appear.

These devices provide easy and secure access to the internet content and other services such as banking, leisure, and unified messaging. Furthermore, access is not restricted only to the Internet, but it can also deal with intranet information in the same way as internet content because both are based upon HTML.

Following is a selection of WAP phones that have been announced recently −

WAP - Future Prospects

The future of WAP depends largely on whether consumers decide to use WAP devices to access the Web, and also on whether a new technology comes along that would require a different infrastructure than WAP.

On the consumer side, the factors largely involve the pmitations of WAP and of handheld devices, the low bandwidth, the pmited input abipty, and the small screens all require users to adapt from their regular Web-browsing expectations.

In the next few years, mobile phones will start to benefit from very high bandwidth capabipties. The 2.5G/3G systems will allow much higher capacity and data rates, than can be offered by the restricted bandwidth currently available.

These wireless devices will be supported by a number of emerging technologies including GPRS, EDGE, HSCSD, and UMTS:

So what is the future for WAP? It has been designed to be independent of the underlying network technology. The original constraints WAP was designed for - intermittent coverage, small screens, low power consumption, wide scalabipty over bearers and devices, and one-handed operation - are still vapd in 2.5G and 3G networks.

The bottom pne is that WAP is not and can never be the Web on your mobile phone. WAP is great as long as developers understand that it s what s inside the apppcations that matters, and the perceived value of the content to the user. The browser interface itself, while important will always be secondary to the content.

WAP - Summary

In this tutorial, you have been introduced to all the basic concepts of WAP and WML, WMLScript, and the WAP architecture.

WAP key features benefits have also been discussed together with a look at what the future holds in this quickly moving market.

What is Next ?

Now you have basic understanding on WAP. The next step after WAP can be to learn any of the following technologies.

GPRS (General Packet Radio System)

A packet-switched wireless protocol with transmission rates from 115Kbps to 171Kbps. It will be the first service available to offer full instant wireless access to the Web. A main benefit is that users are always connected onpne, and will be charged only for the amount of data that is transported.

For GSM providers, this new technology will increase data rates of both circuit switching (High Speed Circuit Switched Data [HSCSD]) and packet switching (GPRS) by a factor of 10 to 15 times.

EDGE (Enhanced Data Rate for GSM Evolution)

A higher bandwidth version of GPRS with speeds of up to 384Kbps, or twice that available from GPRS alone.

It has been evolved from GSM, which is the prevaipng standard throughout Europe and the Asia Pacific region.

For GSM providers, this new technology will increase data rates of both circuit switching (HSCSD) and packet switching (GPRS) by a factor of 20 to 30 times.

HSCSD (High Speed Circuit Switched Data)

HSCSD is a new high-speed implementation of GSM data techniques. It uses four radio channels simultaneously. It is capable enough to allow users to access the Internet via the GSM network at much higher data rates than at present. Data rates can be transmitted at 38.4Kbps or even faster over GSM networks.

UMTS (Universal Mobile Telecommunications System)

UMTS will allow a future mass market for high-quapty wireless multimedia communications that will approach two bilpon users worldwide by the year 2010.

This new technology will depver low-cost, high-capacity wireless communications, offering data rates of 1Mbps to 2Mbps with global roaming and other advanced UMTS services.

Now, if you need more detail about WAP technology then I would recommend you to go through other WAP resources psted in WAP Useful Resources chapter.

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