$$\hbox {S}^2$$S2DCC: secure selective dropping congestion control in hybrid wireless multimedia sensor networks

Thanks to the availability of miniaturized camera and microphones, nowadays Wireless Multimedia Sensor Networks (WMSNs) can sense and deliver audio/video signals from a target environment to remote analysis sites. Hence, new opportunity are disclosed for advanced applications in health care, surveillance, military, and traffic monitoring domains, to name a few. But, at the same time, due to the high volume of multimedia streams and the richness of information they bring, WMSNs incur critical issues in terms of congestion control, privacy, and security. These problems can be solved separately by adopting consolidated solutions conceived to address each of them. But one of the pivotal point of optimization in a Wireless Sensor Network is the possibility of exploiting a cross layer design. To bridge this gap, an integrated solution is proposed hereby, namely Secure Selective Dropping Congestion Control $$(\hbox {S}^{2}\hbox {DCC})$$(S2DCC), based on end-to-end ciphering, in-network selective data dropping, scalable multimedia encoding, and hierarchical and hybrid network design. Moreover, an open source implementation of $$\hbox {S}^{2}\hbox {DCC}$$S2DCC has been developed in the Castalia simulator. The main outcomes of the performance evaluation show that $$\hbox {S}^{2}\hbox {DCC}$$S2DCC is able to meet data security and privacy requirements and to improve the quality of the received images at the sink with respect to state of the art solutions.