Paper 2002/016

Content Extraction Signatures

Ron Steinfeld, Laurence Bull, and Yuliang Zheng


Motivated by emerging needs in online interactions, we define a new type of digital signature called a `Content Extraction Signature' (CES). A CES allows the owner, Bob, of a document signed by Alice, to produce an `extracted signature' on selected extracted portions of the original document, which can be verified to originate from Alice by any third party Cathy, while hiding the unextracted (removed) document portions. The new signature therefore achieves verifiable content extraction with minimal multi-party interaction. We specify desirable functional and security requirements for a CES (including an efficiency requirement: a CES should be more efficient in either computation or communication than the simple multiple signature solution). We propose and analyze four CES constructions which are provably secure with respect to known cryptographic assumptions and compare their performance characteristics.

Available format(s)
Public-key cryptography
Publication info
Published elsewhere. Earlier version was published at ICISC 2001.
digital signaturesprivacycontent extraction
Contact author(s)
ron steinfeld @ infotech monash edu au
2002-02-08: received
Short URL
Creative Commons Attribution


      author = {Ron Steinfeld and Laurence Bull and Yuliang Zheng},
      title = {Content Extraction Signatures},
      howpublished = {Cryptology ePrint Archive, Paper 2002/016},
      year = {2002},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.