Robust Secret Sharing for End-to-End Key Establishment with Physical Layer Keys Under Active Attacks

摘要

In recent years, there has been an increasing interest in physical layer key generation. Most of the approaches require that the communication partners who wish to generate a common secret key share a physical channel. That raises the question whether and how physical layer point-to-point keys can be used for a secure end-to-end key exchange over multiple hops. However, a multi-hop communication implies that an advanced attacker model has to be taken into consideration. In former work, we introduced possibilities for an end-to-end key exchange under the consideration of outsiders and passive insiders. Within this paper, we now focus on active insiders. The basic idea is to use a robust secret sharing scheme. We discuss the applicability and security of this method under different attack scenarios. Our investigations show that a secure key exchange is even possible with a high number of attackers in the system. Simulations allow an estimation of the expected costs in terms of communication overhead.