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                                                                       Wireless bank and WML  

                                                                                                                                            Prof : Dr. S.K Chang

                                                                                                                                            Student : Jin Lung Chen  

WML

    Wireless Markup Language (WML) is a page-layout markup language that describes how the content displayed on narrowband devices (e.g., smart digital phones and PDAs) is presented to the user. It is the language defined by WAP and understood by microbrowsers. WML has been designed to offer Internet and Intranet access over narrowband channels, where computing and network resources are limited. As a result, it was designed with the following constraints specific to narrowband transmissions:

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(1)Limited memory and CPU power

        The devices that host WML-based applications ¡V smart digital phones, smart pagers, and PDA's have less memory and computing power than the desktop systems that typically host Internet applications and protocols.

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(2) Small displays

           Narrowband devices such as digital phones have small screen sizes. Not surprisingly, the typical Web page is designed to be displayed on a larger monitor and is virtually unusable when displayed on a PDA or smart phone screen. The central unit of WML, the deck, supports the need for a more modest chunk of information than offered in an XHTML/HTML page. Not just text display but navigation on small handheld devices must be easy, too, and given the range of wireless devices, can range from two-line cards to more graphically complex decks.

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(3) Narrowband network connections

        Wireless devices rely upon narrowband transmissions for transporting information between the broadband Internet infrastructure and the client device. Different software tools are required for this data retrieval than are used within the Internet/Intranet environments. In combination with an existing application server (or by using integrated application server capabilities), dynamic content can be added to WML pages with WMLScript programs.