[Resource Topic] 2008/496: Constructing Variable-Length PRPs and SPRPs from Fixed-Length PRPs

Welcome to the resource topic for 2008/496

Title:
Constructing Variable-Length PRPs and SPRPs from Fixed-Length PRPs

Authors: Debra L. Cook, Moti Yung, Angelos Keromytis

Abstract:

We create variable-length pseudorandom permutations (PRPs) and strong PRPs (SPRPs) accepting any input length chosen from the range of b to 2b bits from fixed-length, b-bit PRPs. We utilize the elastic network that underlies the recently introduced concrete design of elastic block ciphers, exploiting it as a network of PRPs. We prove that three and four-round elastic networks are variable-length PRPs and five-round elastic networks are variable-length SPRPs, accepting any input length that is fixed in the range of b to 2b bits, when the round functions are independently chosen fixed-length PRPs on b bits. We also prove that these are the minimum number of rounds required.

ePrint: https://eprint.iacr.org/2008/496

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .