John Nagle
Gilles Brassard in Montreal has been working on this for a while, and
has a working prototype. Secure against infinite computational power.
As I put it, The Lorg God Himself, given access only to the channel,
couldn't do better than block communications.
Actually, the quantum channel just provices mostly-shared mostly-secret
bits. An interloper cannot monitor undetectably, so the communicators
can resolve errors between them, then use the number of detected errors
to compute an upper bound on the eavesdropper's knowledge and throw
away some of the bits to get a shorter, but secure (eavesdropoer's
knowledge limited by 2^-n bits, where n is the number of bits above the
minimum required that are thrown away) shared random bit string.
Then you can use this for one-time pads, secure authentication, etc.
Neat stuff.
--
-Colin
co...@eecg.toronto.edu (Colin Plumb) writes:
>In article <#dxlh8...@netcom.com> na...@netcom.com (John Nagle) writes:
>> Scientific American (July 1992, page 100) notes briefly that
>>Charles Bennett at IBM's Watson Research Center has built a device for
>>transmitting a random number safely using the Einstein-Podolsky-Rosen
>>effect. This is a concept so wierd that I won't even try to describe it.
>>I suggest reading the article...
>Gilles Brassard in Montreal has been working on this for a while, and
>has a working prototype...
See Chapter 6 "Quantum Cryptography" in Brassard's book "Modern Cryptolgy",
which is #325 in the Springer-Verlag Lecture Notes in Computer Science series.
A note for the chapter says it "was written with Charles H. Bennett".
Besides having fun stuff like this, the book is a good introduction/survey.
Its ISBNs are: 3-540-96842-3 and 0-387-96842-3.
- Harry Carter (h...@world.std.com)
-- This .sig for rent. No reasonable offer refused! --
It would seem that the UK edition of Scientific American is somewhat
different than the US edition ... it doesn't appear to have the note on the
above device (it only goes upto page 96!). If someone could summaries it
for me I would greatly appreciate it.
Tim
--
Tim Wilkinson E-mail: t...@cs.city.ac.uk
Systems Architecture Research Centre, Fax: +44 71 477 8587
City University, London, UK. Tel: +44 71 477 8551
It's on page 78, in the main text, not a box.
Anyone in the US want to compare contents, so we can learn what we're
missing in our edition ?
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