WAP Architecture - I

WAP is positioned at the convergence of three rapidly evolving network technologies, wireless data, telephony, and theInternet.

Both the wireless data market and the Internet are growing very quickly and are continuing to reach new customers. Theexplosive growth of the Internet has fuelled the creation of new and exciting information services.

Most of the original technology developed for the Internet has been designed for desktop and larger computers andmedium to high bandwidth, generally reliable data networks. Mass-market, hand-held wireless devices present a moreconstrained computing environment compared to desktop computers.

Because of fundamental limitations of power andform-factor, mass-market handheld devices tend to have:
· Less powerful CPUs,
· Less memory (ROM and RAM),
· Restricted power consumption,
· Smaller displays, and
· Different input devices (e.g., a phone keypad).

Similarly, wireless data networks present a more constrained communication environment compared to wired networks.Because of fundamental limitations of power, available spectrum, and mobility, wireless data networks tend to have:
· Less bandwidth,
· More latency,
· Less connection stability, and
· Less predictable availability.

Mobile networks are growing in complexity and the cost of all aspects of providing value-added services is increasing.In order to meet the requirements of mobile network operators, solutions must be:
· Interoperable – terminals from different manufacturers communicate with services in the mobile network;
· Scaleable – mobile network operators are able to scale services to customer needs;
· Efficient – provides quality of service suited to the behaviour and characteristics of the mobile network;
· Reliable – provides a consistent and predictable platform for deploying services; and
· Secure – enables services to be extended over potentially unprotected mobile networks while still preserving theintegrity of user data; protects the devices and services from security problems such as loss of confidentiality.

Many of the current mobile networks include advanced services that can be offered to end-users. Mobile networkoperators strive to provide advanced services in a useable and attractive way in order to promote increased usage of themobile network services and to decrease the turnover rate of subscribers.

Standard features, like call control, can beenhanced by using WAP technology to provide customised user interfaces. For example, services such as callforwarding may provide a user interface that prompts the user to make a choice between accepting a call, forwarding toanother person, forwarding it to voice mail, etc.

The nature of wireless devices is that they are inherently mobile. This mobility introduces new opportunities forservices that are sensitive to mobility and can provide location-dependent information. The WAP specifications andarchitecture capitalise on this unique aspect of wireless devices by including mobility as part of the application model.

The WAP specifications address mobile network characteristics and operator needs by adapting existing networktechnology to the special requirements of mass-market, hand-held wireless data devices and by introducing newtechnology where appropriate.

The WAP specifications will accommodate a range of devices, from devices that provide very basic functionality todevices that continue to expand their capabilities. This motivates an architecture where functionality may be moved todifferent locations within the network as appropriate, i.e. either to devices or to network servers as necessary.