WAP stands for Wireless Application Protocol. This is one of areas of interest. Do read on to know more about this technology...
Important Note:
The URL of my WAP Site is http://www.praveenks.com/wap/index.wml
If you have a WAP enabled cell phone or device, then you can check out my WAP Site by pointing your device to the URL mentioned above.
To see the WAP version of this website, you may use the SmartPhone Emulator provided by Yospace. Please click on the link below to use the Emulator: http://www.yospace.com/spedemo.html
Once you are there, you can choose any of the several phone emulators given. However, I would recommend that you choose the Nokia 7110 Media Phone or the Yospace YoPad models.
The Opera Web Browser is WAP enabled. If you are using it, then you can just copy and paste the above URL into the Address Bar.
1. What is WAP?
The Wireless Application Protocol (WAP) is a global standard developed to make Internet services available for mobile users. It provides a uniform technology platform with consistent content formats for delivering Internet and Intranet based information and services to digital mobile phones and other wireless devices. Even though WAP is based on Internet technology, WAP and the Internet live side by side. A company or a person that has an Internet site can make the information available for mobile users by transforming the pages into WAP pages.
2. History of WAP
In 1995, Ericsson initiated a project whose purpose was to develop a general protocol called Intelligent Terminal Transfer Protocol (ITTP) to enable value added services on mobile networks. During 1996 and 1997, Motorola, Nokia, and Unwired Planet (at present Phone.com) launched similar concepts. Unwired Planet presented Handheld Device Markup Language (HDML) and Handheld Device Transport Protocol (HDTP). Just as Hyper Text Markup Language (HTML) is used on the WWW, HDML is used for describing content and user interface, but it is optimised for wireless Internet access from handheld devices with small displays and limited input facilities. In the same manner HDTP could be considered to be a wireless equivalent of the standard Internet Hyper Text Transport Protocol (HTTP), i.e. a lightweight protocol to perform client/server transactions. In March 1997, Nokia officially presented the Smart Messaging concept especially designed for handheld GSM devices. The communication between the mobile user and the server containing Internet information uses Short Message Service (SMS) and a markup language called Tagged Text Markup Language (TTML) similar to HDML. To avoid clash among these varied technologies and to develop a global wireless protocol specification, these four companies co-founded the WAP Forum on June 26, 1997. Thus, WAP was born.
3. WAP Architecture
WAP is designed in a layered fashion in order to be extensible, flexible, and scalable. The WAP-stack basically is divided into five layers:
The WAP layered architecture enables other services and applications to utilise the features of the WAP stack through a set of well-defined interfaces.
3.1 WAP Application Environment (WAE)
The uppermost layer in the WAP stack, the Wireless Application Environment (WAE) provides an environment that enables a wide range of applications to be used on wireless devices. WAE includes a micro-browser environment containing the following functionality: Wireless Markup Language (WML), WMLScript, Wireless Telephony Application (WTA, WTAI) and Content Formats.
3.2 The Other Layers
WSP is the interface between WAE and the rest of the protocol stack. It is a binary version of HTTP 1.1 with additions such as: capability negotiation, header caching, long-lived sessions, session suspend and resume etc. WTP is responsible for control of transmitted and received messages. WTP works with three different message classes: Unreliable "send", Reliable "send" and Reliable "send" with reliable result message. WTLS is a security protocol based upon the industry-standard Transport Layer Security (TLS) protocol, formerly known as Secure Sockets Layer (SSL). It provides the following features: Data integrity, Privacy, Authentication and Denial-of-service protection. WDP is the base of the WAP protocol stack and it provides a consistent interface to the upper layers of the stack. It hides the characteristics of different bearers and provides port number functionality.
4. What is WML?
WML stands for Wireless Markup Language. WML is WAP’s analogy to HTML used on the WWW. WML is based on the Extensible Markup Language (XML).
WML uses a deck/card metaphor to specify a service. A card is typically a unit of interaction with the user, that is, either presentation of information or request for information from the user. A collection of cards is called a deck, which usually constitutes a service. This approach ensures that a suitable amount of information is displayed to the user simultaneously since inter-page navigation can be avoided to the fullest possible extent.
Key features of WML include:
· Variables
· Text formatting features
· Support for images
· Support for soft-buttons
· Navigation control
· Control of browser history
· Support for event handling (for e.g. telephony services)
· Different types of user interactions, e.g. selection lists and input fields
WML can be binary encoded by the WAP Gateway/Proxy in order to save bandwidth in the wireless domain.
5. How do we view WAP sites?
To view WAP sites, we need a WAP browser. Normal web browsers like the one you are using right now can't be used to view WAP pages. There are various WAP browsers available like Klondike, WinWap etc. However, these WAP browsers have to be downloaded and installed on your computer.
The second option is to use an Online Emulator. These Emulators convert the WML pages into HTML pages. Thus, we are able to see the contents of a WAP page even though we are using a normal Web browser. What actually happens is that on entering the URL and pressing the Go! Button, the control is transferred to a JavaScript. The JavaScipt then calls a CGI program on the server side. The CGI program converts the WML code into HTML code and sends back the modified code back to the browser. Thus, what we see on the Emulator is the HTML version of the WML page and not the actual WML page.
To see the WAP version of this website, you may use the SmartPhone Emulator provided by Yospace. Please click on the link below to use the Emulator: http://www.yospace.com/spedemo.html
Once you are there, you can choose any of the several phone emulators given. However, I would recommend that you choose the Nokia 7110 Media Phone or the Yospace YoPad models.
