Spam Filtering with Cryptographic Ad-hoc E-mail Addresses

This paper presents an ad-hoc e-mail address service system which employs a cryptographic algorithm for the generation of ad-hoc addresses. The addresses are associated with mail filter rules and subscribers´ original address undisclosed to public. The presented algorithm enables mail transfer agents to filter incoming mails by extracting filter rules from ad-hoc addresses, and thus requires no database to store filter rules for the addresses. The practical usability of the presented system has been tested to major Internet services which requires e-mail addresses.