This talk is the fifth one in the seminar series „Reading the Crypto Classics“ for the summer term 2018. The idea of this seminar is to jointly read classical milestone papers in the area of cryptography, to discuss their impact and understand their relevance for current research areas. The seminar is running as an Oberseminar, but at the same time meant to be a joint reading group seminar of the CROSSING Special Interest Group on Advanced Cryptography with all interested CROSSING members being invited to participate.
This issue will cover the paper
Reingold, Trevisan, Vadhan: „Notions of Reducibility Between Cryptographic Primitives“ (TCC 2004), DOI:10.1007/978-3-540-24638-1_1
with the following abstract:
„Starting with the seminal paper of Impagliazzo and Rudich, there has been a large body of work showing that various cryptographic primitives cannot be reduced to each other via “black-box” reductions. The common interpretation of these results is that there are inherent limitations in using a primitive as a black box, and that these impossibility results can be overcome only by explicitly using the code of the primitive in the construction.
In this paper we revisit these negative results, give a more careful taxonomy of the ways in which “black-box reductions” can be formalized, strengthen some previous results (in particular giving unconditional impossibility results for reductions that were previously only shown to imply P≠ NP), and offer a new interpretation of them: in many cases, there is no limitation in using a primitive as a black box, but there is a limitation in treating adversaries as such. In particular, these negative results may be overcome by using the code of the adversary in the analysis.“