An Authentication Code against Pollution Attacks in Network Coding

TL;DR

This paper introduces an unconditionally secure authentication code for network coding that effectively detects and prevents pollution attacks, enhancing network integrity and throughput.

Contribution

It presents a novel authentication scheme that is secure against both outsiders and insiders, enabling in-transit verification without decoding.

Findings

The scheme improves multicast throughput and goodput.

It effectively detects and discards malicious packets in transit.

The approach is applicable to file distribution systems.

Abstract

Systems exploiting network coding to increase their throughput suffer greatly from pollution attacks which consist of injecting malicious packets in the network. The pollution attacks are amplified by the network coding process, resulting in a greater damage than under traditional routing. In this paper, we address this issue by designing an unconditionally secure authentication code suitable for multicast network coding. The proposed scheme is robust against pollution attacks from outsiders, as well as coalitions of malicious insiders. Intermediate nodes can verify the integrity and origin of the packets received without having to decode, and thus detect and discard the malicious messages in-transit that fail the verification. This way, the pollution is canceled out before reaching the destinations. We analyze the performance of the scheme in terms of both multicast throughput and goodput, and show the goodput gains. We also discuss applications to file distribution.