000K utf8 1100 $c2009 1500 eng 2050 urn:nbn:de:101:1-201203133371 3000 Kürtz, Klaas Ole 3010 Schnoor, Henning 3010 Wilke, Thomas 4000 A Simulation-Based Treatment of Authenticated Message Exchange [Kürtz, Klaas Ole] 4209 Simulation-based security notions for cryptographic protocols are regarded as highly desirable, primarily because they admit strong composability and, consequently, a modular design. In this paper, we give a simulation-based security definition for two-round authenticated message exchange and show that a concrete protocol, 2AMEX-1, satisfies our security property, that is, we provide an ideal functionality for two-round authenticated message exchange and show that 2AMEX-1 realizes it securely. To model the involved public-key infrastructure adequately, we use a joint-state approach. 4950 https://nbn-resolving.org/urn:nbn:de:101:1-201203133371$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/macau_mods_00001843 5051 004