On the Security of Lattice-based Physical-layer Network Coding Against Wiretap Attacks

We consider Gaussian-channel networks that employ lattice-based physical-layer network coding (PNC) as their routing strategy. Under the assumption that the communication is subject to the adversarial attacks in the form of wiretapping, we address data security from an information-theoretic viewpoint. To this end, we first examine how data transfer in PNC-based networking is vulnerable against wiretapping attacks, and then we show that it, due to the structured codebook employed in PNC, is possible to apply the already available lattice coset coding to obstruct the attackers in obtaining any information from the data communicated over the network. Several wiretap attack scenarios targeted to such networks are considered and possible solutions are discussed.