Cryptology ePrint Archive: Report 2003/233

Public Key Steganography

Luis von Ahn and Nicholas J. Hopper

Abstract: Informally, a public-key steganography protocol allows two parties, who have never met or exchanged a secret, to send hidden messages over a public channel so that an adversary cannot even detect that these hidden messages are being sent. Unlike previous settings in which provable security has been applied to steganography, public-key steganography is information-theoretically impossible. In this work we introduce computational security conditions for public-key steganography similar to those introduced by Hopper, Langford and von Ahn for the private-key setting. We also give the first protocols for public-key steganography and steganographic key exchange that are provably secure under standard cryptographic assumptions.

Additionally, in the random oracle model, we present a protocol that is secure against adversaries that have access to a decoding oracle (the steganographic equivalent of CCA-2 adversaries).

Category / Keywords: foundations /

Date: received 6 Nov 2003

Contact author: hopper at cs cmu edu

Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation

Version: 20031108:052417 (All versions of this report)

Short URL: ia.cr/2003/233

Discussion forum: Show discussion | Start new discussion