Comment Re:Umm... I'm confused (Score 1) 858
It's anonymous. Details are left out. Keys go basically like this:
Public & private key pair each for You and Alice -- that's 2 mated keys apiece.
Take message "Hello." and scramble with a public OR private key.
Now you have gunk "09D7C1".
ONLY the mated public/private key can decrypt and reveal "Hello.".
When you send to Alice you encrypt with her public key so that ONLY she can decrypt -- with her private key.
But first you encrypt with YOUR private key! (AND THEN encrypt THAT with Alice's public key.)
So then:
Alice gets the gunk.
(operation 1) Decrypts with her private key.
Just more gunk.
(operation 2) Decrypts THAT with YOUR public key.
Now she sees "Hello.".
Operation 1 is the true encryption: only Alice's private key mates to successfully decrypt.
Operation 2 is the authentication: only your public key mates to successfully decrypt, which proves that it was encrypted with YOUR private key -- Alice is assured it was sent by you AND it hasn't been modified.
These are not the *precise* details of a Bitcoin transaction; yet this *IS* the technology.
NONE of the key material is sent: the reciever must find the package and understand which keys to use to decrypt -- you tell Alice "I just sent you something". On the network it IS just anonymous gunk.
Details omitted include tracing by network activity: even though the package is anonymouse & safe, if you know the computer that sent it is Sony's head office, then you know someone sent it from that machine
And of course the underlying security of encryption & authentication lies in the pseudo-inability to crack the keys. It IS possible, and heavy government machines do it. All this IS addressed in Bitcoin's design in a form.