%0 Journal Article %T Some decidability result for logic constructed for checking user authentication protocols %A L¨˘szl¨® Aszal¨®s %A Philippe Balbiani %J Journal of Computer Science and Control Systems %D 2008 %I Editura Universit??ii din Oradea %X The core of our paper is a general purpose logical system for reasoning about user authentication protocols. Proposed as an extension of the propositional epistemic logic by dynamic operators, the potential usefulness of our calculus for protocol verification is illustrated with examples. %K authentication protocol %K modal logic %K dynamic %U http://electroinf.uoradea.ro/reviste%20CSCS/documente/JCSCS_2008/JCSCS_2008_1_Aszalos_1.pdf