A cryptographic key management architecture for dynamic 6LowPan networks

Abstract

Wireless sensor networks are becoming an important facilitator for the Internet of Things. These embedded devices can harvest different types of information such as temperature, pressure and humidity, which offer important data for making decisions regarding various applications such as healthcare, logistics and smart homes. Different sensors working together act as a local sensor network. With the advent of the new 6LowPan standard the sensor nodes can even participate in Internet communications, opening up even more possibilities. The downside is that these networks are more prone to intrusion by unwanted parties. Furthermore implementing security is not straightforward due to the constrained nature of the sensor nodes, although different solutions have been proposed. One of the remaining and most challenging issues is the key management problem. In this paper, we propose a symmetric key management scheme for wireless sensor networks that uses tamper-proof hardware for key generation and distribution. The scheme requires no deployment knowledge before enrolling and makes use of a trusted central entity for key negotiation to provide end-to-end security. Our implementation and evaluation were performed on the tiny Zolertia Z1 hardware platform, running Contiki-OS. The performance and security evaluation show * This work is funded by the IWT-TETRA project 120105: 6LoWPAN -Towards zeroconfiguration for wireless building automation.

Applications and Techniques in Information Security

“…This paper builds on the scheme that was presented in [4]. In the remainder of the paper, we refer to that scheme as the 'original scheme'.…”

“…In this section, we present our wireless key pre-distribution mechanism for efficient security bootstrapping of wireless sensor nodes. This work aims to improve the user friendliness and security trade-offs for the wired bootstrapping mechanism described in [4]. We start with an analysis of the wired bootstrapping system in Sect.…”

“…Furthermore, loading the keys into the nodes prior to deployment is not possible due to absence of network association. The original scheme solves this problem by using a wired bootstrapping mechanism to initialize the nodes with the necessary security information during node placement [4]. After a thorough study we noticed that the described method comes with some disadvantages.…”

“…The next step requires the user to manually approve the stored key requests. Similar to the original scheme the user makes use of the tablet interface to either acknowledge or decline a request [4]. For each approved request the CE creates a unique security device in its database which contains all the security information 3 needed by the requesting node.…”

“…It uses the µIPv6 stack for 6LoWPAN communications. The scheme builds on a previously proposed scheme using wired bootstrapping for the enrollment of new network nodes [4]. We identify the shortcomings of this scheme and propose a new method for key pre-distribution.…”