Abstract. The Domain Name System (DNS) has been the naming service of the Internet for more than 20 years. It is the foundation of virtually all other distributed service. The deficiencies of DNS with respect to performance, availability, and reliability are well known. We want to systematically improve DNS by (1) measuring DNS performance, (2) evaluating past proposals, and (3) try to come up with a new architecture for DNS. SEDNS is a system in which we investigate various design ideas to speed up DNS requests and improve availability, reliability, and security.