Message Authentication Codes: Formalism

This lecture covers the concept of message authentication codes (MACs) and their formalism, focusing on the case study of mobile telephony. The instructor explains the process of processing with extra data, CCM, GCM mode, and GCM. Various aspects such as misuse attacks on GCM, authenticated modes to remember, and security notions related to integrity and authentication are discussed. The lecture delves into topics like commitment schemes, key derivation functions, pseudorandom generators, cryptographic hash functions, and the security of message authentication codes against key recovery and forgery. A case study on mobile telephony, specifically GSM architecture, slang, protocol, peer authentication, encryption, privacy protections, and improvements in 3G mobile telephony, is presented.