Advances in Cryptology

In the summer of 1981 Allen Gersho organized the first major open co, ifcrcncc c ci devoted to cryptologic research This meeting, Crypto '81, was held at the Universitc nl California campus in Santa Barbara Since then the Crypto' conference has become dii annual event These are the proceedings of the fifth1 of these confercnces, Crypt0 XS Each section of this volume corresponds to a session at the meeting.