A traitor tracing system enables a publisher to trace a pirate decryption box to one of the secret keys used to create the box. We present a traitor tracing system where ciphertext size is "constant, " namely independent of the number of users in the system and the collusion bound. A ciphertext in our system consists of only two elements where the length of each element depends only on the security parameter. The down side is that private-key size is quadratic in the collusion bound. Our construction is based on recent constructions for fingerprinting codes.
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