# Re: Public Key encryption methods

*From*: Unruh <unruh-spam@xxxxxxxxxxxxxx>*Date*: 6 Jun 2006 21:51:39 GMT

Matthijs Hebly <heeb@xxxxxxxxxxxxxxxx> writes:

Hi all,

just out of curiosity:

All Public Key encryption methods that I know of are based on some

hard-to-solve mathematical problem (like factoring large composites is

hard (unless you're JSH)).

Are there Public Key encryption methods that are fundamentally

different, in that they do *not* work with such hard-to-solve problems?

Uh, if they did not work with some hard to solve problem, they would be

easy to solve, and the crypto system would not be worth much.

Ie, ALL crypto systems work with hard to solve problems.

Note that "hard to solve" for a crypto system may be very different from

things like NP. A problem which scales line L^10000 where L is the length

of the input is in P and not usually called hard, but it may still be hard to

solve in the crypto sense.

Thanks,

M..

**Follow-Ups**:**Re: Public Key encryption methods***From:*Matthijs Hebly

**References**:**Public Key encryption methods***From:*Matthijs Hebly

- Prev by Date:
**Re: RSA: more than one secret exponent d exists ???** - Next by Date:
**Re: BitCrypt Explained** - Previous by thread:
**Re: Public Key encryption methods** - Next by thread:
**Re: Public Key encryption methods** - Index(es):