TKK | Tietoverkkolaboratorio | Opetus

Will WAP Flop?

WAP as a technique


WAP as a technique

WAP services Competition




WAP stands for Wireless Application protocol. Both Internet and mobile communication grow very fast, but they are using different operating system, signaling protocol etc. Some kind of integration is needed of these two systems. The goal of WAP is to provide wireless internet-like services on information devices that have limited display and data capabilities, such as mobile phone. WAP is developed to be a standard means of information transportation. It uses the wireless telephony application server to get access to the Internet from mobile devices. WAP is hardware, software platform and network independent. Essential parts of the existing Internet protocols are used for WAP. But everything is optimized because of limited bandwidth. For example, the header is minimized and compressed binary format is used instead of plain text.

WAP protocol stack

WAP is a stack of protocol, which implements requirement for different layers.

  1. On application layer, the Wireless Application Environment (WAE) offers the software platform environment for application software. It uses Wireless Markup Language (WML) as WAP'S markup language. WML provides navigational support, data input, hyperlinks, text and image presentation etc. It works much like HTML for WWW. Wireless Telephony Application (WTA) is used to control telephony functions of the device from WML. URL addressing is used for WAP applications
  2. On the session layer, Wireless Session Protocol (WSP) is implemented. It provides securely exchaging typed data between client and server and supports WAP sessions in parrallel with voice or data connections. Transport service will be based on WTP and is compatible with TCP/IP and UDP transport service.
  3. On the transaction layer, Wireless Transaction Protocol (WTP) is used between WSP and WTLS. It includes WTP/D which is datagram oriented protocol and WTP/C which is connection oriented transport protocol.
  4. On security layer, Wireless Transport Layer Security protocol (WTLS) does all the cryptography oriented features of WAP.
  5. On transport layer, Wireless Datagram Protocol(WDP) is used to process datagrams from upper layers to formats required by different physical layers.
The WAP architecture

The WAP architecture can be seen from the following figure

WAP architecture
Illustration from WAP Forum

A mobile device sends a WML message to the WAP proxy server with a specified URL. WAP gateway works as a link between a mobile network and the Internet. It converts data from HTTP to WAP and vice versa so that any conventional WWW server may be used as the document origin server with WAP. The WAP gateway requires for and gets the file or application in the location the URL indicates from Web server. All the contents that aren't in the

WML format are converted in this format by the HTML/WML filter and then are sent to the mobile device.

Humberto Granados Sánchez
Yan Li
Leena Pohja

Tämä sivu on tehty Teletekniikan perusteet -kurssin harjoitustyönä.
Sivua on viimeksi päivitetty 05.12.2000 19:04