What is Wireless Application Protocol (WAP)?
Wireless Application Protocol (WAP) is a specification for a set of communication protocols to standardize the way wireless devices, such as mobile phones and radio transceivers, can be used for internet access, including email, the web, newsgroups and instant messaging. While internet access was possible before the introduction of WAP, different manufacturers have used varying technologies; WAP promised interoperability between these technologies.
WAP was conceived in 1997 by Ericsson, Motorola, Nokia and Unwired Planet (now Phone.com) at an event known as the WAP Forum. In 2002, the WAP Forum became the Open Mobile Alliance (OMA).
The Wireless Markup Language (WML) was used to create pages that can be delivered using WAP.
There were other approaches to an industry standard besides WAP, including i-Mode.
How the WAP works
WAP describes a protocol suite. This standard is designed to create interoperability between WAP equipment, such as mobile phones that use the protocol, and WAP software, such as WAP-enabled web browsers and network technologies.
These standards optimize mobile experiences that were previously limited by the capabilities of handheld devices and wireless networks. WAP does this through:
- the WML format for pages, which can be delivered using WAP;
- internet standards that are efficient for wireless environments, such as Extensible Markup Language (XML), user datagram protocol (UDP) and Internet Protocol (IP), which are based on standards such as HTML, HTTP and TLS but without the large amounts of data;
- binary transmission that allows for greater data compression; and
- optimization for high latency, low connection stability and low bandwidth through using a lightweight protocol stack.
WAP model and layers
WAP model. The WAP model works similar to the traditional client-server model but uses an additional WAP gateway as an intermediary between the client and server. This gateway translates the WAP device request, from a microbrowser, into an HTTP URL request and sends it to the server over the internet.
When the server returns a response, the WAP gateway processes and sends the webpage to the WAP mobile device as a WML file that is compatible with microbrowsers.
WAP protocol stack. The WAP standard describes the following protocol stack for interoperability of WAP devices, equipment, software and other technologies, including:
- Wireless Application Environment (WAE) for mobile device specifications and programming languages such as WML;
- Wireless Session Protocol (WSP), which manages connection suspensions and reconnections;
- Wireless Transaction Protocol (WTP), which manages transaction support for requests and responses to servers;
- Wireless Transport Layer Security (WTLS) for managing privacy, authentication and data integrity through public key cryptography; and
- Wireless Datagram Protocol (WDP), which is an adaptation layer for consistent data formats in the other layers, and it defines how data flows to the sender, from the receiver.
Why use WAP?
Introduced in 1999, WAP proposed benefits for wireless network operators, content providers and end users:
- Wireless network and mobile phone operators. WAP was designed to improve existing wireless data services such as voicemail while also enabling the development of additional new mobile applications. These applications can be introduced without any additional infrastructure changes or phone modifications.
- Content providers. WAP creates a market for additional applications and mobile phone functionalities for third-party application developers to exploit. Writing applications in WML was proposed as a new programming language for developers to create effective mobile device applications.
- End users. Mobile phone users were stated to benefit from easy, secure access to online services, such as banking, entertainment, messaging and other information, on mobile devices. Intranet information -- such as corporate databases and business applications -- was also to be accessed through WAP.
Despite these proposed benefits, WAP did not experience widespread adoption in many countries, and its use declined significantly around 2010, due to widespread HTML compatibility in mobile phones.
For more information on current mobile multimedia technology, read about how multimedia data and 5G are driving network transformation.