Secure and Self-stabilizing Clock Synchronization in Sensor Networks

Abstract

Abstract. In sensor networks, correct clocks have arbitrary starting offsets and nondeterministic fluctuating skews. We consider an adversary that aims at tampering with the clock synchronization by intercepting messages, replaying intercepted messages (after the adversary's choice of delay), and capturing nodes (i.e., revealing their secret keys and impersonating them). We present the first self-stabilizing algorithm for secure clock synchronization in sensor networks that is resilient to such an adversary's attacks. Our algorithm tolerates random media noise, guarantees with high probability efficient communication overheads, and facilitates a variety of masking techniques against pulse-delay attacks in the presence of captured nodes.

Self-stabilizing TDMA Algorithms for Wireless Ad-Hoc Networks without External Reference

“…Lemmas 3 and 4 refer to the cases when τ > 2∆ and τ > max{4δ, ∆ + 1} for which Lemma 5 shows that the communication delay (during convergence) of the former case is δ times shorter than the latter. The proof shows that we can apply the analysis of [12], because the back off process of a passive node counts r unused timeslots, where r is a random choice in [1, 3∆]. The lemma statement denotes the latency period by := (1 − e −1 ) −1 .…”

Mapping Systems Security Research at Chalmers

“…In [32], we presented the first secure and self-stabilizing algorithm for clock synchronization in sensor networks. Clustering organizes a network into groups that, e.g., can be used for forming backbones, for routing, for aggregating data, and for building hierarchies that allow for scaling.…”

Interacting Urns Processes for Clustering of Large-Scale Networks of Tiny Artifacts

“…We assume that the system has access to a self-stabilizing clock synchronization mechanism (such as [31,32]), that facilitates the agreement on a particular time slot once in every T time slot. The algorithm makes sure that in that time slot (1) every tiny artifact stores the values of all urns in out put (see line 30), (2) no tiny artifact draws a ball from its urn (see line 31), (3) every tiny artifact restarts its state (by assigning the urn with the initial value of one black ball and one white ball; see line 32).…”