Security of Random Key Pre-distribution Schemes With Limited Tamper Resistance

Key pre-distribution (KPD) schemes, are inherently trade-offs between security and complexity, and are perhaps well suited for securing large-scale deployments of resource constrained nodes without persistent access to a trusted authority (TA). However, the need to offset their inherent security limitations, calls for some degree of tamper-resistance of nodes. Obviously, if absolute tamper-resistance is guaranteed, KPD schemes are rendered secure. In practice, however, tamperresistance will have some limitations which will be exploited by attackers. In this paper, we analyze the security of deployments of random key pre-distribution schemes based on some assumptions on the “extent of tamper-resistance.” We argue that a “limited extent of tamper resistance” when used in conjunction with a mechanism for “periodic key updates,” drastically improves the security of (especially random) KPD schemes.