Abstract

With the recent development in communication technologies, the field of cryptography for information confidentiality has significantly developed, and various ciphers have been proposed, implemented, and utilized. Most modern cryptography is based on end-to-end IP communication for one-to-one communication, and many cryptographic algorithms have been developed. In IP communication, although broadcast and multicast communication exist as one-to-many or many-tomany communication, cryptographic algorithms for multiparty communication are still underdeveloped, and research on Broadcast Encryption, which is a cryptographic scheme with a fixed sender, is actively being conducted. In this paper, we propose the requirements of multicast cryptography as a feasible multi-person cryptosystem over IP multicast, in which any user can be a sender at any time. In addition, a prototype cipher is proposed.