IFIP/SEC2000, being part of the 16th IFIP World Computer Congress (WCC2000), is being held in Beijing, China from August 21 to 25, 2000. SEC2000 is the annual conference of TCll (Information Security) of the International Federation of Information Processing. The conference focuses on the seamless integration of information security services as an integral part of the Global Information Infrastructure in the new millenniUm. SEC2000 is sponsored by the China Computer Federation (CCF), IFIP/TCll, and Engineering Research Centre for Information Security Technology, Chinese Academy of Sciences (ERCIST, CAS). There were 180 papers submitted for inclusion, 50 papers among them have been accepted as long papers and included in this proceeding, 81 papers have been accepted as short papers and published in another proceeding. All papers presented in this conference were reviewed blindly by a minimum of two international reviewers. The authors' affiliations of the 180 submissions and the accepted 131 papers range over 26 and 25 countries or regions, respectively. We would like to appreciate all who have submitted papers to IFIP/SEC2000, and the authors of accepted papers for their on-time preparation of camera-ready fmal versions. Without their contribution there would be no conference. We wish to express our gratitude to all program committee members and other reviewers for their hard work in reviewing the papers in a short time and for contributing to the conference in different ways. We would like to thank Rein Venter for his time and expertise in compiling the fmal version of the proceedings.