Advantage (cryptography)

<p>In <a href="/facts/Cryptography/e94PEVau">cryptography</a>, an adversary's advantage is a measure of how successfully it can attack a cryptographic <a href="/facts/Algorithm/fnl5NmRt">algorithm</a>, by distinguishing it from an idealized version of that type of algorithm.  Note that in this context, the "<a href="/facts/Adversary_(cryptography)/X211CFfE">adversary</a>" is itself an algorithm and not a <a href="/facts/Person/XD3Hhqup">person</a>.  A cryptographic algorithm is considered secure if no adversary has a non-<a href="/facts/Negligible_function/yHCYQj4J">negligible</a> advantage, subject to specified bounds on the adversary's computational resources (see <a href="/facts/Concrete_security/fCFpMNnm">concrete security</a>).  "Negligible" usually means "within <a href="/facts/Big_O_notation/weFFjSWg">O</a>(2−p)" where p is a <a href="/facts/Security_parameter/Xbqeyh60">security parameter</a> associated with the algorithm.  For example, p might be the number of bits in a block cipher's <a href="/facts/Key_(cryptography)/5W5PAmT4">key</a>.
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Advantage (cryptography) open-in-new

Advantage (cryptography)