Random oracle: Difference between revisions

Revision as of 05:25, 2 June 2024

Revision as of 03:44, 7 September 2024

Line 23:

== Domain separation ==

{{main|___domain separation}}

A single oracle may be treated as multiple oracles by pre-pending a fixed bit-string to the beginning of each query (e.g., queries formatted as "1|x" or "0|x" can be considered as calls to two separate random oracles, similarly "00|x", "01|x", "10|x" and "11|x" can be used to represent calls to four separate random oracles). This practice is usually called '''[[___domain separation''']]. ''Oracle cloning'' is the re-use of the once-constructed random oracle within the same proof (this in practice corresponds to the multiple uses of the same [[cryptographic hash]] within one algorithm for different purposes).{{sfn|Bellare|Davis|Günther|2020|p=3}} Oracle cloning with improper ___domain separation breaks security proofs and can lead to successful attacks.{{sfn|Bellare|Davis|Günther|2020|p=4}}

== Limitations ==