Non-repudiation is one of the most important security services. In this paper we present a novel non-repudiation technique, called server-supported signatures,
. It is based on one-way hash functions and traditional digital signatures. One of its highlights is that for ordinary users the use of asymmetric cryptography is limited to signature verification.
is efficient in terms of computational, communication and storage costs. It also offers a degree of security comparable to that of existing techniques based on asymmetric cryptography.
