Deeply Embedded XML Communication: Towards an Interoperable and Seamless World

Current consumer electronics devices do not interoperate and are hard to use. Devices use proprietary, device-specific and inflexible protocols. Resources across device classes, such as personal computers and home appliances cannot be taken advantage of. Even recent efforts to connect sensors into networks concentrate on new, ad-hoc protocols that segregate the low-cost devices into their own little world. If all classes of devices could speak the same language, they could talk directly to each other in ways natural to the application without artificial technical barriers. This would allow easily creating seamless applications that aggregate the capabilities of all the electronics. The interoperation adds value to all the devices. Extensible Markup Language (XML) Web Services were conceived to solve the e-business interoperation problem. After decades of failed attempts with EDI, SNA, DCOM, CORBA, and other similar technologies, XML and its communication specification SOAP has proven itself to be a viable technology. If XML is good for e-business, could it also be good for embedded systems communication? This paper argues that XML and SOAP indeed can be useful in small devices. Solutions to performance questions are available and techniques are outlined here. New unique challenges, such as heterogeneous configuration, privacy and security issues, and real-time requirements (e.g. for gaming) are identified and solutions outlined. A prototype implementation for low-cost microcontrollers is described with numbers included. Categories and Subject Descriptors C.3 [Special-purpose and application-based systems]: Real-time and embedded systems C.2.1 [Network architecture and design]