Notions of Security
In their foundational paper, Goldwasser, Micali, and Rivest lay out a hierarchy of attack models against digital signatures:
- In a key-only attack, the attacker is only given the public verification key.
- In a known message attack, the attacker is given valid signatures for a variety of messages known by the attacker but not chosen by the attacker.
- In an adaptive chosen message attack, the attacker first learns signatures on arbitrary messages of the attacker's choice.
They also describe a hierarchy of attack results:
- A total break results in the recovery of the signing key.
- A universal forgery attack results in the ability to forge signatures for any message.
- A selective forgery attack results in a signature on a message of the adversary's choice.
- An existential forgery merely results in some valid message/signature pair not already known to the adversary.
The strongest notion of security, therefore, is security against existential forgery under an adaptive chosen message attack.
Read more about this topic: Digital Signature
Famous quotes containing the words notions of, notions and/or security:
“the full analysis of the notions of saying something and understanding what one said inevitably involves a concept which, as I will show in detail, essentially corresponds to the Cartesian idea of thought.”
—Zeno Vendler (b. 1921)
“Your notions of friendship are new to me; I believe every man is born with his quantum, and he cannot give to one without robbing another. I very well know to whom I would give the first place in my friendship, but they are not in the way, I am condemned to another scene, and therefore I distribute it in pennyworths to those about me, and who displease me least, and should do the same to my fellow prisoners if I were condemned to a jail.”
—Jonathan Swift (1667–1745)
“The contention that a standing army and navy is the best security of peace is about as logical as the claim that the most peaceful citizen is he who goes about heavily armed. The experience of every-day life fully proves that the armed individual is invariably anxious to try his strength. The same is historically true of governments. Really peaceful countries do not waste life and energy in war preparations, with the result that peace is maintained.”
—Emma Goldman (1869–1940)