Anonymous Credit

[Ben Laurie]

David Wagner wrote:
> 
> Ben Laurie  wrote:
> >Interesting ... this reminds me of a protocol Angelos Keromytis and I
> >were discussing recently (during IETF, in fact) to allow the efficient
> >authentication of a stream of data without having to wait for the end.
> >We feel sure this must have already been invented, but neither of us is
> >aware of any previous publication. Here it is:
> >
> >At the head of the stream, present a signature for X_0. X_0 is the hash
> >of the concenation of the first block of data and X_1. X_1 is the hash
> >of the concatenation of the second block and X_2, and so forth.
> >[...]
> >Note that this is only applicable to a stream whose contents were known
> >to the sender in advance, of course - the situation we were envisaging
> >was downloading and unpacking packages on the fly, and wanting to be
> >sure they haven't been subverted.
> 
> This sounds like the scheme proposed by Rosario Gennaro and Pankaj Rohatgi
> at CRYPTO'97.  See <http://citeseer.nj.nec.com/gennaro97how.html> for more.

It is indeed the "off-line" scheme they propose. Thanks for the info.

Cheers,

Ben.

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