A Framework for Flexible Packet Processing in Heterogeneous Sensor Networks

Monitoring technologies leveraging on heterogeneous sensor networks are becoming increasingly important in almost every application scenario where pervasive data collection is needed. In current sensor networks deployments, many low-level protocols and functions details dependent on used network technology are explicitly handled at application level, in a cross-layer fashion. This is not a critical issue in homogeneous networks, where services are provided by a unique network platform. However, in applications where several multi-purposes heterogeneous sensor networks coexist and interoperate, managing low-level details at application level can be a complex and time-consuming task, distracting the development of the back-end application logic. In order to overcome these limitations, it is necessary to de-couple low-layer details from application layer in order to achieve lower integration efforts, improve code reusability and gain higher flexibility. This paper describes the design of a framework for sensor network message processing and interpretation, focusing on issues related to the integration between sensor networks gateways (the so-called "Sink nodes") and back- end applications. The proposed solution relies on NetPDL, an application-independent, XML-based packet format description language [4]. The advantages of this approach are highlighted by presenting three use-cases of the proposed solution.