Efficient Key Pre-distribution for 6LoWPAN

Abstract

The Internet of Things is imposing an evolution of the capabilities of wireless sensor networks. The new IP-based 6LoWPAN standard for low power sensor networks allows an almost seamless connection of local sensor networks to the Internet. This makes it easier to connect local sensor networks to data processing servers or to provide web services for those networks. On the other hand, the connection to the Internet also opens doors for unauthorized nodes to become part of the local network. Therefore, measures need to be taken to protect the information that is captured and communicated within the local network. The most important challenge in doing so, is the implementation of a key management architecture, keeping in mind that the sensor nodes are constrained in power consumption and data storage capacity. This paper builds on a previously proposed symmetric key management scheme for 6LoWPAN networks. The original scheme is based on wired bootstrapping for the enrollment of new nodes, while the paper at hand proposes a wireless method for key pre-distribution. We analyze the original wired scheme and its shortcomings. Next, we propose the new wireless scheme and elaborate on the practical implementation on Zolertia Z1 nodes running Contiki-OS. We show that it is possible to provide end-to-end security using wireless bootstrapping within the constraints of the tiny nodes at hand.