End to end secure anonymous communication for secure directed diffusion in IoT

The Internet of Things (IoT) paradigm integrates smart devices and sensors to build systems such as smart homes, healthcare etc. However, sensors are prone to several attacks from malicious insiders as well as outsiders. Thus to secure IoT based applications, providing anonymous communication and end to end data secrecy while preventing impersonation and preserving privacy of nodes are important concerns. The existing solutions on achieving anonymous communication or data secrecy, either cannot achieve complete anonymity or have large storage or communication overhead which is difficult to implement in resource-constrained sensor based IoT. So, in this work we propose an Improved Secure Directed Diffusion (ISDD) protocol targeting a low-overhead solution for all the said security goals. The ISDD uses pseudonyms to conceal the node's real identity thereby ensuring anonymous communication. It also uses bilinear pairing to derive shared keys which are then used to generate multiple encryption layers over the plaintext message. Thus ISDD achieves end to end data secrecy, privacy of nodes and also effectively prevents malicious adversaries from impersonating a legitimate node. Finally, through security analysis we establish the aforementioned claims while achieving additional features compared to other state-of-the-art competing schemes. We also compute different overheads which are compared with two existing schemes. Results show significant improvement of ISDD in communication and storage overhead over both the competing schemes at the cost of marginal higher computation while keeping energy consumption within an acceptable limit.