In the WAP wireless providers version 1, defined in 1999, the language of presentation of content is WML, or Wireless Markup Language. The WAP protocol stack 1 is not directly compatible with the cellular phones Internet: WSP (Wireless Session Protocol), WTP (Wireless Transaction Protocol), WTLS (Wireless wifi Transport Layer Security) and WDP (Wireless Datagram Protocol). WDP is the transport layer, with equivalent functionality to the Internet UDP protocol, and relies on the services of the “carrier” WAP, depending on the network using the mobile terminal. WAP 1 also defines the interface for access by applications to the telephony functions of the terminal with WTAI (Wireless Telephony Application Interface), and also an easy language “scripting”, WMLScript, which is based on ECMAScript / JavaScript.
The incompatibility of the WAP email protocol stack 1 with the Internet calls for a gateway node to an intermediary cellular phone plan chooser in communication between a WAP terminal and a WAP content server residing on the cellular providers Internet. WAP 1 has been strongly criticized for several reasons, including poor graphic (graphic monochrome WBMP, Wireless Bitmap), the differences in implementations of the WAP terminals from different manufacturers, and a potential security problem due wifi to WTLS is not that strong, and besides, not being compatible with the layers of security used on the Internet, the WAP gateway content must be clear.
The new version of WAP, WAP 2.0, is present in the new generation mobile phones (since 2004). This version is a re-used WAP XHTML-MP (XHTML Mobile Profile), a subset of XHTML that includes basic XHTML and WCSS (WAP CSS), a subset of CSS2 more specific to certain mobile extensions such as languages for presentation of content such as improved support for graphics (including color). This ensures that the Blackberry cell phone design of content with WAP 2.0 is very similar to design content for Blackberry the WWW browser in mobile devices. Blackberry phones As for the protocols used in the transport layer using TCP and the Application, HTTP. Thus, WAP 2.0 has adopted Internet protocols. WAP 2.0 also specifies options in TCP and HTTP in order to improve the performance of such protocols on mobile communications cell phone plan chooser networks. The security mechanisms used and are compatible with the Internet so that security issues are resolved WAP 1. The WAP gateway is not strictly necessary in WAP 2.0, but their presence may have useful features such as web caching and to support the TCP and Blackberries HTTP options above.

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