Multi-receiver authentication code for network coding

Systems exploiting network coding 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 with unconditionally secure multi-receiver authentication codes designed for network coding. Our scheme is robust against pollution attacks from outsiders and even from a coalition of k - 1 malicious insiders. With our authentication code, intermediate nodes can verify the message integrity and origin of the packets received without having to decode and thus detect and discard the malicious packets in-transit that fail the verification. This way, the pollution is canceled out before reaching the destinations.