The Holey Grail: A special score function for non-binary traitor tracing

B.  Skoric; J. -J.  Oosterwijk; J.  Doumen

Paper 2013/420

The Holey Grail: A special score function for non-binary traitor tracing

B. Skoric, J. -J. Oosterwijk, and J. Doumen

Abstract

We study collusion-resistant traitor tracing in the simple decoder approach, i.e. assignment of scores for each user separately. We introduce a new score function for non-binary bias-based traitor tracing. It has three special properties that have long been sought after: (i) The expected score of an innocent user is zero in each content position. (ii) The variance of an innocent user's score is~1 in each content position. (iii) The expectation of the coalition's score does not depend on the collusion strategy. We also find a continuous bias distribution that optimizes the asymptotic (large coalition) performance. In the case of a binary alphabet our scheme reduces exactly to the symmetrized Tardos traitor tracing system. Unfortunately, the asymptotic fingerprinting rate of our new scheme decreases with growing alphabet size. We regret to inform you that this grail has holes.

Metadata

Available format(s): PDF
Publication info: Published elsewhere. Unknown where it was published
Keywords: traitor tracing
Contact author(s): b skoric @ tue nl
History: 2013-07-02: received
Short URL: https://ia.cr/2013/420
License: CC BY

BibTeX

@misc{cryptoeprint:2013/420,
      author = {B.  Skoric and J. -J.  Oosterwijk and J.  Doumen},
      title = {The Holey Grail: A special score function for non-binary traitor tracing},
      howpublished = {Cryptology {ePrint} Archive, Paper 2013/420},
      year = {2013},
      url = {https://eprint.iacr.org/2013/420}
}