With the increasing use of small portable computers, wireless networks, and satellites, a trend to support computing on the move has emerged; this trend is known as mobile computing or nomadic computing.
Also referred to as anytime/anywhere computing, mobile computing has several interesting and important applications for business (such as instant claim processing and e-commerce), telecommunications and personal communications, national defense (tracking troop movements), emergency and disaster management, real-time control systems, remote operation of appliances, and accessing the Internet.
Since a user may not maintain a fixed position in such environments, the mobile and wireless networking support allowing mobile users to communicate with other users (fixed or mobile) becomes crucial.
A possible scenario may involve several different networks that can support or can be modified to support mobile users.
Mobile middleware can be defined as an enabling layer of software that is used by applications developers to connect their applicationswith different mobile networks and operating systems withoutintroducing mobility awareness in the applications.
The use of middleware may allow applications to run with better response times and much greater reliability.
Typically, middleware uses optimization techniques, such as header compression, delayed acknowledgements, and concatenation of several smaller packets into one, to reduce the amount of traffic on the wireless networks.
Currently, many different wireless access technologies exist that are not interoperable. Designing and building network and business applications for each technology would be a nightmare for developers.
This problem, combined with redesigning all websites to support downloading by mobile users is even more difficult. Even if all of this can be achieved, the information content still has to be adapted for transmission over wireless links and is an effort to solve these problems:it allows development of applications that are independent of the underlying wireless access technology.
WAP also adapts the existing website contents for transmission over wireless links and display on mobile devices.
Wireless local area networks are designed to provide coverage in a small area, such as a building, hallway, park, or office complex by extending or replacing wired LANs (such as Ethernet).
The main attraction is the flexibility and mobility supported by a wireless LAN; bandwidth considerations are secondary.