Executive Summary : | A general way of showing that a cryptographic construction is indistinguishable from its idealized counterpart is the Random Oracle Model, introduced by Bellare and Rogaway, where some component of the construction is replaced by a random oracle, and then this modified construction is proved to be secure. However, in a particular instantiation of the construction using a function family as the component might still prove to be insecure if the attacker has access to the underlying primitives of this function family. The more general notion of indifferentiability is introduced by Maurer to show security for these kinds of constructions. We aim to investigate constructions like the Confusion Diffusion Network, six-round Feistel, and HMAC under this notion of indifferentiability security and certain other weaker variants. |