Programming Applications with the Wireless Application Protocol: The Complete Developer's Guide (WAP, Band 3) - Hardcover

Über die Autorin bzw. den Autor

Steve Mann is President of Creative Digital Publishing Inc., www.cdpubs.com, a leading provider of technical information for the handheld and mobile computing industries. He has 25 years of experience in the computer industry and is a frequent contributor to many wireless publications.

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The authoritative programming guide to the WAP standard from the creators of this breakthrough technology

The Wireless Application Protocol (WAP) is the key force turning mass market wireless phones into Internet companions. These lightweight, inexpensive smart phones are well equipped for high–quality voice communication, modest–bandwidth (9–14 Kbps) data communication, seamless Internet connectivity, and access to Internet services via built–in WAP microbrowsers. Written with the creators of WAP, this book/CD–ROM package will guide you through the process of creating software for WAP–enabled cell phones and handheld devices.

Steve Mann presents practical tools, code snippets, and complete applications that will help you best utilize WAP. He introduces you to the Wireless Markup Language (WML) that you′ll be able to use to create WAP applications. And you′ll learn about the key features of WMLScript, including the lightweight procedural capabilities and function libraries it adds to WML. Mann also:
∗ Takes you step by step through the process of creating a real–world
WAP application
∗ Describes techniques for optimizing WAP applications
∗ Shows how to create more sophisticated and interesting applications using graphics
∗ Discusses the issues you′ll need
∗ in order to build WAP applications that will work around the world
∗ Explains some of the advanced extensions to WAP
∗ Suggests future directions in which WAP may evolve

The CD–ROM includes:
∗ All the source code from the book
∗ A searchable version of the
∗ unabridged WAP standard
∗ The latest release of Phone.com′s WAP Software Developer′s Kit, containing the tools and documentation required to build real–world WAP applications

Phone.com is a leading provider of WAP software and SDKs to developers, wireless carriers, and phone manufacturers. Phone.com cofounded the WAP Forum in 1997 and chaired the WAP Forum′s first Board of Directors. Phone.com′s software architects, who contributed to this book, chair WAP′s technical specification committees. For more information about Phone.com and the Wireless Application Protocol, please visit www.phone.com

For more information about the Wireless Application Standard,please refer to the Official Wireless Application Protocol: The Complete Standard with Searchable CD–ROM published by John Wiley & Sons, ISBN 0–471–32755–7 at www.wiley.com/compbooks/WAP

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Extract from Chapter 1

Introducing WAP CHAPTER 1

T here are more than 300 million cell phone users in the world. There are also mil-lions of Internet users in the world. According to all the experts, the number of users of both of these technologies will continue to grow rapidly for several years. Cell phones are ideal for staying in touch with the rest of the world (assuming you have coverage, but that's another story). They are small, lightweight, and inexpensive. Most countries have one or more cellular voice networks. Less-developed countries are also building cellular telephone infrastructures because it's easier and quicker to deploy a cellular network than a traditional wired network. Clearly, wireless telephony will become the dominant form of voice communication in the world.

Internet access is also transforming the way the world operates. E-mail and the World Wide Web are becoming the lingua franca of modern living. Families use e-mail to stay in touch. Businesses use the Web to market and sell products. You can have focused, timely news delivered to your computer. You can sell personal items at one of the many auction sites, conducting a virtual garage sale. You can buy and sell stocks, and check airline schedules, international weather, and local movie listings. There are literally tens of thousands of resources on the Internet.

Cellular telephony is a mobile technology. You carry the phone with you, placing and receiving calls from around the world. To date, Internet access has primarily been a desktop activity done with a physical telephone line and a modem. Mobile Internet access has been a dream but not a reality. Although it's possible to achieve wireless Internet access using a wireless modem with a laptop or handheld computer, or with certain types of two-way pagers, these solutions are not ideal for many reasons: device size and weight, battery life, and cost, for instance.

There are a variety of forces at work that are causing a convergence of cell phone and Internet technologies: * The cost of buying and using cell phones is decreasing. In many parts of the world, wireless voice communication is less expensive than traditional wired voice communication. As a result, cell phone usage is surging. * Both computer and cell phone technologies are becoming more powerful. We are witnessing tremendous improvements in memory, battery, and central processing unit (CPU) technologies, making it possible for both telephone and computer manufacturers to deliver substantially more horsepower for less money. * Internet use is surging. More and more people are realizing that there is tremendous value to using the Internet, both for communication and for content. It's natural to want access to that value, all the time, without having to carry a full-blown computer or deal with the complexities of figuring out how to add wireless capabilities to that computer. * People want information when they need it, not just when they are near a desktop computer. The cell phone is the most appropriate device for receiving information on demand. Also, more than 300 million people already carry them and millions of new cell phone users are signing up each year. * Cell phones are becoming smarter. They are no longer just devices for voice communication. Manufacturers are starting to put more memory and more powerful processors in cell phones. Once you do that, it's natural to include more powerful applications such as contact management programs, to-do lists, and other personal productivity software. * Cellular networks are becoming more capable. For several years now, it's been possible, with some difficulty, to use analog cellular networks for data communications. The new digital cellular networks are much more suited for both voice and data traffic. * Internet and cell phone use is converging on flat-rate pricing. Both markets previously charged in increments of minutes (cell phones) or hours (Internet). Flat-rate, unlimited Internet pricing is now the norm. Flat-rate wireless voice and data pricing is starting to emerge in the United States; it has been available for certain types of services for several years in parts of Europe and Asia. Predictable fixed costs make it much easier for potential wireless data consumers to take the plunge.

As a result of all these trends, cell phone manufacturers are starting to deliver smart phones, telephones with full-blown programmable computers embedded in the hardware. Computer device manufacturers are starting to build handheld computers with wireless communications capabilities. Both markets are converging on the same spot: small, lightweight, inexpensive mobile computing devices that are equally suitable for high-quality voice communication; modest-bandwidth (5 - 10 Kbps) data communication; seamless Internet connectivity; access to Internet services like e-mail and content; and general-purpose, programmable computing devices that can run custom applications.

The WAP Forum Long ago, and far away in Internet years, in the early 1990s, it was becoming clear to the major cell phone manufacturers that wireless voice and data and the Internet would eventually converge. They started working on technologies to foster that convergence. At the same time, a Silicon Valley start-up, formerly Unwired Planet, now called Phone.com, also started working on technologies for that convergence.

Phone.com's HDML (Handheld Device Markup Language) served as the basis for Wireless Markup Language (WML). The company, headquartered in Silicon Valley, with overseas operations in Japan and the United Kingdom, is currently a publicly held provider of WAP-compatible microbrowser and WAP gateway technologies. Phone.com's products are in use by leading global wireless vendors, including AT& T Wireless, Bell Atlantic-Mobile, GTE Wireless, Mitsubishi, Panasonic, QUALCOMM, Samsung, Siemens, and others.

In June of 1997, the three largest cell phone manufacturers - Ericsson, Motorola, and Nokia - and Unwired Planet announced the WAP (Wireless Application Protocol) Forum, a nonprofit organization for creating standards for delivering Internet access to consumer-class wireless devices. Open to all interested parties, particularly content developers, device manufacturers, carriers, and infrastructure providers, the WAP Forum's goals are to: * Foster the delivery of Internet content and advanced data services to wireless telephones and other mobile wireless devices. These services can be simple generic services like wireless e-mail and Web access. They also include specific solutions for vertical markets like dispatching and field service. * Create a global protocol specification that works on all wireless networks in all parts of the world. WAP includes a protocol stack definition that is easily adapted to Short Message Service (SMS), GSM Unstructured Supplementary Service Data (USSD), Cellular Digital Packet Data (CDPD), and other networks. * Enable the creation of content and applications that scale across a wide range of networks and devices. The WAP Application Environment (WAE) includes definitions for user interface (UI) independent applications that can run, unchanged, on a variety of devices with different characteristics. * Embrace and extend existing standards and technologies whenever possible and appropriate. Specifically, the WAP Forum borrows heavily from existing Internet standards while solving problems specific to wireless networks. This includes a strong focus on making all WAP technologies and applications readily internationalizable.

In order to meet these goals, the WAP Forum had to carefully consider the characteristics of the target devices and the wireless environment in which they operate. Despite the increasing power and capabilities of cellular telephones, they are still consumer devices selling in a very price-sensitive market. Every manufacturing dollar...