Abstract
Keywords: AEAD; Authenticated encryption; CAESAR competition; Cryptographic standards; Fast software encryption; Modes of operation; OCB We describe OCB3, the final version of OCB, a blockcipher mode for authenticated encryption (AE). We prove the construction secure, up to the birthday bound, assuming its underlying blockcipher is secure as a strong-PRP. We study the scheme's software performance, comparing its speed, on multiple platforms, to a variety of other AE schemes. We reflect on the history and development of the mode. Author Affiliation: (1) Computer Science Department, California State University, 6000 J Street, 95819, Sacramento, California , USA (2) Department of Computer Science, Kemper Hall of Engineering, University of California, 95616, Davis, California , USA (b) rogaway@cs.ucdavis.edu Article History: Registration Date: 05/11/2021 Received Date: 12/20/2019 Accepted Date: 09/14/2020 Online Date: 07/27/2021 Byline: