[IWAR] CRYPTO Rivest; new techniques

From: Mark Hedges (hedgesat_private)
Date: Sat Mar 21 1998 - 17:44:58 PST

  • Next message: Mark Hedges: "[IWAR] US BANKS,BIOMETRICS - SEAL bill would allow banks to require"

    A nagging question strikes me:
    If both parties must share the secret winnowing authentication key, how do
    you transport the key securely without public/private encryption?
    Transportation of the encrypting key by insecure channels gives
    public/private key encryption a practical advantage over shared key methods
    like one-time pads and this method. If winnowing/chaffing could transport
    the secret authentication key securely without encryption, it'd be "the
    bomb", as they say. The authentication key could be integrated into
    off-the-shelf products with checksums and signatures for authenticity, but
    the manufacturer can still tap.
    Is there a way to transfer the shared secret securely without encryption?
    If not, cryptofascist legislation would still hurt. Joe Everybody can't use
    diplomatic pouches.
    Mark Hedges
    Anonymizer, Inc.
    >Chaffing and Winnowing: Confidentiality without Encryption
    >                        Ronald L. Rivest
    >                        MIT Lab for Computer Science
    >                        March 21, 1998
    >                        http://theory.lcs.mit.edu/~rivest/chaffing.txt
    >There is a secret key shared by the sender and the receiver to
    >authenticate the origin and contents of each packet---the legitimate
    >receiver, knowing the secret authentication key, can determine that a
    >packet is authentic by recomputing the MAC and comparing it to the
    >received MAC.  If the comparison fails, the packet and its MAC are
    >automatically discarded.

    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 13:06:44 PDT