On the Use of XML for Data Access in Networks of Embedded Devices

The paper deals with embedded networking and distributed embedded systems, which is a key area of research over the last years. It presents a custom protocol for data access in embedded devices - CNDEP (Controller Network Data Extracting Protocol). The presented work is based on the presumption that all data exchanged should be encoded in universal, platform independent format - XML. The XML-based version of the protocol CNDEP should provide interoperation between embedded devices, considered as components. The underlying communication is UDP/IP/Ethernet, which ensures good integration of embedded devices with other information systems. The protocol CNDEP is designed as a part of Multi-tier Client/Server System for Distributed Measurement and Control. It is used for data transfer in data producing tier. The transfer delays for the protocol are measured and compared to the non-XML implementation for evaluation of the effectiveness and efficiency of the realization.