Title
Provably Secure Steganography
Abstract
Steganography is the problem of hiding secret messages in "innocent-lookingrdquo public communication so that the presence of the secret messages cannot be detected. This paper introduces a cryptographic formalization of steganographic security in terms of computational indistinguishability from a channel, an indexed family of probability distributions on cover messages. We use cryptographic and complexity-theoretic proof techniques to show that the existence of one-way functions and the ability to sample from the channel are necessary conditions for secure steganography. We then construct a steganographic protocol, based on rejection sampling from the channel, that is provably secure and has nearly optimal bandwidth under these conditions. This is the first known example of a general provably secure steganographic protocol. We also give the first formalization of "robustrdquo steganography, where an adversary attempts to remove any hidden messages without unduly disrupting the cover channel. We give a necessary condition on the amount of disruption the adversary is allowed in terms of a worst case measure of mutual information. We give a construction that is provably secure and computationally efficient and has nearly optimal bandwidth, assuming repeatable access to the channel distribution.
Year
DOI
Venue
2009
10.1109/TC.2008.199
Computers, IEEE Transactions
Keywords
Field
DocType
cryptographic protocols,probability,steganography,channel rejection sampling,complexity-theoretic proof technique,covert channel,cryptographic formalization,innocent-looking public communication,probability distribution,provably secure steganography,secret message hiding,steganographic protocol,Encryption,Reducibility and completeness,Security and Protection,Steganography,covert channels,provable security.
Steganography,Computational indistinguishability,Computer security,Computer science,Theoretical computer science
Journal
Volume
Issue
ISSN
58
5
0018-9340
Citations 
PageRank 
References 
19
1.71
11
Authors
3
Name
Order
Citations
PageRank
Nicholas Hopper1146995.76
Luis von Ahn23461346.66
John Langford35392353.60