I-HARPS: An Efficient Key Pre-distribution Scheme

We introduce an efficient random key pre-distribution scheme (RKPS) whose performance is 2 to 3 orders of magnitude better than schemes of comparable complexity in the literature. This dramatic improvement is achieved by increasing insecure storage complexity (for example using external flash memory). The proposed scheme is a combination of the Kerberos-like key distribution scheme (KDS) proposed by Leighton and Micali, and random key pre-distribution schemes based on subset intersections. We also investigate a simple security policy, DOWN (decrypt only when necessary) (which along with very reasonable assurances of tamper resistance / read-proofness could ensures that no more than one secret an be exposed by tampering with a node), and its effect on the security of key pre-distribution schemes. The proposed scheme lends itself well for efficient implementation of the DOWN policy, and therefore in practice could be a secure and efficient alternative to more complex conventional key distribution schemes.