And how would you send the private one to several people who may be living in different parts of the world?
You would never do that. You're supposed to keep the private key secret and share the public key. Someone sending you a message would use your public key to encrypt it and then you'd use your private key to decrypt it. That's the whole point of public key encryption, so that it's easy to share exchange keys, without requiring secure means to do so. With public key encryption there are 2 keys and one can decrypt what the other has encrypted. But either key cannot decrypt what it has encrypted.
Sounds reasonable, but..... if I send an e-mail encrypted with my secret private key and the person at the other end has the public key then surely if my message is intercepted by anyone who has that public key then it can be read by anyone who has that public key. The "interceptor" may not be able to read a response to my original post, only I can do that with my secret and private key, but they surely would be able to read whatever *I* post. No? :-) . When you send someone an encrypted email, you use their public key and
Basil Chupin wrote: they use their private key to decrypt. As I mentioned above, when they send you a message, they use your public key and you then use your private key. The private key is used to decrypt something that has been encrypted with the public key. The private key can also be used to create a digital signature that can be verified with the corresponding public key. So, if you want to exchange encrypted email with someone, you first have to exchange public keys and you don't care who sees them. You could even post them in public forums such as this. You never, ever exchange private keys. BTW, with the X.509 digital certificates, just signing an email was enough to send someone your public key. You'll often see PGP users attaching their public key to a message. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org