A Lightweight Buyer-Seller Fingerprinting Protocol

A buyer-seller fingerprinting protocol can enable a seller to successfully identify a traitor from a pirated copy, while preventing the dishonest seller from framing an innocent buyer. Existing protocols often create a large computation and band-width overhead for two reasons: one is a lot of asymmetric ci-phers operations are performed and the other is the uniquely fingerprinted copies are sent to each buyer by unicasting which is not a bandwidth efficient way. In this article, we present a lightweight buyer-seller fingerprinting protocol, in which, the asymmetric cipher operations are avoided and the uniquely fin-gerprinted copies generating process is shifted from the seller side to the buyer side which can avoid a high load at the seller side. Furthermore, the digital content is sent to all buyers by multicasting which can reduce the bandwidth requirement dra-matically.