Wireless Application Protocol (WAP) What's It All About?

by Charlie Schick

Wireless Application Protocol (WAP) is a standard for the transmission and presentation of information over a wireless connection. With WAP, wireless service providers can provide high-level interactive information services to subscribers over the same voice network. Why does this matter? In this tutorial, I will give an overview of WAP and why it may be important.

WAP Forum
In June of 1997, the major cellular phone manufacturers, Nokia, Ericsson, Motorola, and WAP creator, Phone.com (formerly Unwired Planet) joined to form the WAP Forum. The Forum is an industry group responsible for managing and extending the WAP standard and facilitating the adoption of WAP. Membership represents more than 90% of the world wireless market, covering carriers, developers, manufacturers, and content providers. The future of WAP is in the hands of the WAP Forum.

What is WAP? WAP is a standard for transmission and presentation of wireless information to devices of all kinds. The communication protocol is based on HTTP to allow easy integration into the current internet. The display language, called Wireless Markup Language (WML), is based on the XML standard. Indeed, the World Wide Web consortium has entered an agreement with the WAP Forum to guarantee the compatibility between WML and XML. Because WAP is based on the HTTP and XML, traditional tools, such as web servers and XML tools, can be used to develop and deploy WAP. And because WAP isn't wedded to a wireless transport standard (e.g., GSM, TDMA) it can work over practically any wireless network.

But WAP is more than just a variation on the current web. WAP was designed considering the restrictions of wireless connections (low bandwidth, less connection stability) and mobile devices (small screen, no dialpad, limited CPU, limited battery life). For example, communication between the WAP micro-browser and the WAP server has a low overhead, leading to conservation of bandwidth and CPU cycles. Also, there is a re-establishment protocol that allows sessions to be suspended and resumed without too much cost to bandwidth.

Finally, WAP contains the framework to include other services, such as call control for telephony applications and voice and data integration, data push capabilities, and other services not yet defined by a standard.

Why is WAP good?
Previous implementations of wireless internet access tried to shoehorn the graphic-rich web into a tiny screen, on a slow device, over a slow connection. Other implementations required a separate server or proxy software and heavy content redesign. WAP allows the content provider to re-purpose its content through XML. This allows users to access site data via an HTML or WAP browser. For example, Onebox and uReach allow users full access to their unified messaging accounts, for both reading and composing messages. ThinkMobile makes their news headlines available over WAP. I was told by one of the ThinkMobile engineers that the WAP content just required a script to re-render the page into WML—the data is the same as on their news page. As vendors began offering WAP-enabled devices, more and more sites are going to offer WAP-based services.

WAP services
PDA and PC users can install a WAP browser on their machines. I am currently testing the OmniSky wireless service with the Palm V and have successfully used a WAP browser (from AU-System) in the Palm OS over a wireless connection. But cellular phone service providers are the most visible proponents of a WAP world. The WAP poster child in the U.S. has been Sprint's NeoPoint 1000. On the Sprint system using the WAP browser, users can search the net, buy books, and find various forms of information. And Sprint, at the head of the WAP-pack, is able to add significant value to their existing voice offerings with WAP. Through the WAP service, Sprint generates more billable minutes, creates a new relationship with users (which affects customer retention), and provides access to enhanced services already existing on the web—WAP-enabled services such as Onebox or uReach.

Final comment
In a few years we will treat the wireless internet and WAP no differently than we treat cellular phones and the internet now—they will be essential tools and they will be ubiquitous. But right now, WAP content is like the early days of the net—very little content and not all that useful. I heard the comment that wireless internet is like drug rehab for people hooked on wired internet (that's me). WAP definitely fits this description until useful things can be done.

But soon, the WAP world will reach a mass that will drive an exponential growth in WAP content and applications. My feeling is that for now, WAP is interesting. But in 6 months, when there are more useful applications available to WAP devices, such as unified messaging, WAP will be worth the effort and expense. Indeed, the more cross-dressers who sit in the WAP and HTML worlds, such as uReach's unified messaging, the more useful WAP devices become.

As an indication of the importance of applications in the WAP world, Phone.com, the creator of WAP, recently gobbled up Onebox and other online application service providers. These purchases position Phone.com as prime application service provider in the wireless and WAP market. As it is, most WAP content is dull and there is little reason to believe that this will change. Wireless handsets are currently too limited to offer more than a monochrome screen and text applications. WAP's fate will be determined by its functionality and consumer desire to stay connected while on the move.