Enhanced blind decoding of Tardos codes with new map-based functions

TL;DR

This paper introduces a new blind decoder for Tardos codes that improves performance by using a map-based hypothesis testing approach, eliminating the need for prior collusion channel estimation.

Contribution

The paper proposes a novel, simple, and numerical decoder for Tardos codes that outperforms existing symmetric decoders without requiring collusion channel estimation.

Findings

Better performance than symmetric Tardos decoder for common attack channels

No prior estimation of collusion channel needed

Simpler and more numerical accusation functions

Abstract

This paper presents a new decoder for probabilistic binary traitor tracing codes under the marking assumption. It is based on a binary hypothesis testing rule which integrates a collusion channel relaxation so as to obtain numerical and simple accusation functions. This decoder is blind as no estimation of the collusion channel prior to the accusation is required. Experimentations show that using the proposed decoder gives better performance than the well-known symmetric version of the Tardos decoder for common attack channels.