From cell phones to personal digital assistants to telematic systems in automobiles, mobile computing surfaces in so many different forms that application development across disparate devices is a difficult task.
From cell phones to personal digital assistants to telematic systems in automobiles, mobile computing surfaces in so many different forms that application development across disparate devices is a difficult task. This is why Web serviceswhich are by definition interface-agnosticare particularly well-suited to mobile devices.
Whats more, Web services enable typically resource-constrained mobile devices to smoothly benefit from the storage and processing advantages of the systems that host a given Web service.
Until recently, the limited speed and availability of wireless data networks have hindered the prospects of network services on mobile devices. However, the spread of General Packet Radio Service and 1xRTT-based networks has brightened the outlook for networked mobile devices, and industry players such as Microsoft, Palm Inc. and Sun are preparing Web services offerings to seize these new opportunities.
Microsofts .Net Compact Framework, a subset of the companys .Net Web services platform, is designed to deliver these services to mobile devices. Microsoft provides for the creation of Web services based on the Compact Framework through a Visual Studio .Net component called Smart Device Extensions. Currently, Microsoft provides these extensions, as well as the Compact Framework, in a beta version, which can be downloaded from Microsofts Web site.
Palm has announced separate partnerships with BEA Systems Inc. and IBM to develop Web services solutions for use with BEAs WebLogic Server 7.0 and IBMs WebSphere Everyplace Access. These Web services delivery schemes will center on a forthcoming XML messaging component from Palm called Reliable Transport.
Reliable Transport is slated to support secure messaging in both synchronous and asynchronous transmission modes. Asynchronous communications are vital for mobile devices, which frequently under- go lengthy network connectivity droughts.
Suns plan for bringing Web services to mobile devices comprises its CDC (Connected Device Configuration) and the CVM, or C Virtual Machine, a virtual machine based on Suns J2ME (Java 2 Micro Edition). The CDC communicates with Web services via SOAP and will enable users to create peer-to-peer applications as well.
J2ME is the platform on which Research In Motion Ltd.s BlackBerry 5810 device, as well as various cell phones, are built. These units, along with Sharp Electronics Corp.s Linux-based Zaurus handheld, are likely to be the early consumers of Suns mobile Web services. However, existing mobile Java implementations for Palm and Pocket PC devices should ensure a broad audience for Web services based on this technology.
Cross-platform device support will be a key factor in the success or failure of these mobile Web services schemes. The mobile device space is young and relatively volatile, and its not clear which device platform will dominate or whether such domination is even possible. Java-based systems offer a certain measure of cross-platform support, but, generally, the needs of each device must be taken into account when developing these solutions.