# newbie Q: "Stacked" public key algorithm

*From*: Steffen Köhler <steffen@xxxxxxxxxxx>*Date*: Wed, 13 May 2009 18:33:45 +0200

sorry for the stupid question. Up to now I was just a cryptography user

without really understanding the technique behind, but now I've a question

regarding a solution I'm looking for, a kind of "stacked public key

algorithm"...

Image, a company has a public and a secrect key. Employes also have their

own key pair. The planned scenario is like that:

the employee (Alice) send her public key to the company.

the company "mixes" their own private key with the public key of Alice and

send it back to Alice. Let us call this the "mixed key"

Alice can use this "mixed" key together with her own private key to read

messages with where encrypt with the company public key, means messages

which were "sent do the company".

But Alice should not be able to seperate the company private key again out

of her mixed key, so that she can't give the company private key alone to

somebody else without telling that she was the one who forwarded the

company secret key.

Do you understand, what I mean? Has anybody ever heard about such a

algorithm???

Good question, isn't it?

Any hints are appreciated & many thanks in advance

best regards

Steffen

.

**Follow-Ups**:**Re: newbie Q: "Stacked" public key algorithm***From:*Gordon Burditt

**Re: newbie Q: "Stacked" public key algorithm***From:*Skybuck Flying

**Re: newbie Q: "Stacked" public key algorithm***From:*tom

- Prev by Date:
**Re: Why does SRP (Secure Remote Password) use the username to encrypt the password?** - Next by Date:
**Re: newbie Q: "Stacked" public key algorithm** - Previous by thread:
**SHA-1 collisions now 2^52** - Next by thread:
**Re: newbie Q: "Stacked" public key algorithm** - Index(es):