Cryptology and knot theory?

[Krister Walfridsson <cato@df.lth.se>]

Hej!

I've finally got the time to read "Cyphernomicon", and in chapter 5 
(Cryptology) and 17 (The Future) I found this, which I think looks 
interesting, since I'm interested in computational topology.

    5.5.9. Miscellaneous Abstract Ideas
             [...stuff deleted...]
             - links to knot theory

    17.10.3. Ciphers are somewhat like knots...the right sequence of moves
             unties them, the wrong sequence only makes them more tangled. 
             ("Knot theory" is becoming a hot topic in math and physics
             (work of Vaughn Jones, string theory, etc.) and I suspect
             there are some links between knot theory and crypto.)
 
Has any work been done along those lines?

I did some searches with AltaVista, but I only found Cyphernomicon...

   /Krister