The eighteenth International Workshop on Operator Theory and Applications (IWOTA) was hosted by the Unit for Business Mathematics and Informatics of the North-West University, Potchefstroom, South Africa from July 3 to 6, 2007. The conference was dedicated to Professor Joseph A. Ball on the occasion of his 60th birthday and to Professor Marinus M. Kaashoek on the occasion of his 70th birthday, and we wish to similarly honour them by dedicating this volume of the proceedings to them. TheaimoftheIWOTAmeetingsistobringtogethermathematiciansworking in operator theory and its applications to related ?elds. Each conference therefore has a unique character, depending on the related ?elds chosen by the local or- nizers. In the present case Functional Analysis and Von Neumann algebras were decided on, due to the number of people actively working in those ?elds in South Africa. The meetings are intended to be truly international (the seventeen pre- ous ones were held in 11 di?erent countries) and this conference was no exception, with participants drawn from 17 countries. IWOTA is directed by an international steering committee of 25 members under the guidance of the president I. Gohberg (Tel Aviv), assisted by the Vice PresidentsJ.W.Helton(LaJolla)andM.A.Kaashoek(Amsterdam).TheProce- ings of the IWOTA workshops regularly appear in the Birkhauser .. series: Operator Theory: Advances and Applications, and we thank them for their willingness to continue this cooperation by publishing this volume.

The current IT environment deals with novel, complex approaches such as information privacy, trust, digital forensics, management, and human aspects. This volume includes papers offering research contributions that focus both on access control in complex environments as well as other aspects of computer security and privacy.

The 7th Annual Working Conference of ISMSSS (lnformation Security Management and Small Systems Security), jointly presented by WG 11.1 and WG 11.2 of the International Federation for Information Processing {IFIP), focuses on various state-of-art concepts in the two relevant fields. The conference focuses on technical, functional as well as managerial issues. This working conference brings together researchers and practitioners of different disciplines, organisations, and countries, to discuss the latest developments in (amongst others) secure techniques for smart card technology, information security management issues, risk analysis, intranets, electronic commerce protocols, certification and accreditation and biometrics authentication. W e are fortunate to have attracted at least six highly acclaimed international speakers to present invited lectures, which will set the platform for the reviewed papers. Invited speakers will talk on a broad spectrum of issues, all related to information security management and small system security issues. These talks cover new perspectives on secure smart card systems, the role of BS7799 in certification, electronic commerce and smart cards, iris biometrics and many more. AH papers presented at this conference were reviewed by a minimum of two international reviewers. W e wish to express our gratitude to all authors of papers and the international referee board. W e would also like to express our appreciation to the organising committee, chaired by Leon Strous, for aU their inputs and arrangements.

The Eighth Annual Working Conference of Information Security Management and Small Systems Security, jointly presented by WG11.1 and WG11.2 of the International Federation for Information Processing (IFIP), focuses on various state-of-art concepts in the two relevant fields. The conference focuses on technical, functional as well as managerial issues. This working conference brings together researchers and practitioners of different disciplines, organisations, and countries, to discuss the latest developments in (amongst others) information security methods, methodologies and techniques, information security management issues, risk analysis, managing information security within electronic commerce, computer crime and intrusion detection. We are fortunate to have attracted two highly acclaimed international speakers to present invited lectures, which will set the platform for the reviewed papers. Invited speakers will talk on a broad spectrum of issues, all related to information security management and small system security issues. These talks cover new perspectives on electronic commerce, security strategies, documentation and many more. All papers presented at this conference were reviewed by a minimum of two international reviewers. We wish to express our gratitude to all authors of papers and the international referee board. We would also like to express our appreciation to the organising committee, chaired by Gurpreet Dhillon, for all their inputs and arrangements. Finally, we would like to thank Les Labuschagne and Hein Venter for their contributions in compiling this proceeding for WG11.1 and WG 11.2.

The Eighth Annual Working Conference of Information Security Management and Small Systems Security, jointly presented by WG11.1 and WG11.2 of the International Federation for Information Processing (IFIP), focuses on various state-of-art concepts in the two relevant fields. The conference focuses on technical, functional as well as managerial issues. This working conference brings together researchers and practitioners of different disciplines, organisations, and countries, to discuss the latest developments in (amongst others) information security methods, methodologies and techniques, information security management issues, risk analysis, managing information security within electronic commerce, computer crime and intrusion detection. We are fortunate to have attracted two highly acclaimed international speakers to present invited lectures, which will set the platform for the reviewed papers. Invited speakers will talk on a broad spectrum of issues, all related to information security management and small system security issues. These talks cover new perspectives on electronic commerce, security strategies, documentation and many more. All papers presented at this conference were reviewed by a minimum of two international reviewers. We wish to express our gratitude to all authors of papers and the international referee board. We would also like to express our appreciation to the organising committee, chaired by Gurpreet Dhillon, for all their inputs and arrangements. Finally, we would like to thank Les Labuschagne and Hein Venter for their contributions in compiling this proceeding for WG11.1 and WG 11.2.

The 7th Annual Working Conference of ISMSSS (lnformation Security Management and Small Systems Security), jointly presented by WG 11.1 and WG 11.2 of the International Federation for Information Processing {IFIP), focuses on various state-of-art concepts in the two relevant fields. The conference focuses on technical, functional as well as managerial issues. This working conference brings together researchers and practitioners of different disciplines, organisations, and countries, to discuss the latest developments in (amongst others) secure techniques for smart card technology, information security management issues, risk analysis, intranets, electronic commerce protocols, certification and accreditation and biometrics authentication. W e are fortunate to have attracted at least six highly acclaimed international speakers to present invited lectures, which will set the platform for the reviewed papers. Invited speakers will talk on a broad spectrum of issues, all related to information security management and small system security issues. These talks cover new perspectives on secure smart card systems, the role of BS7799 in certification, electronic commerce and smart cards, iris biometrics and many more. AH papers presented at this conference were reviewed by a minimum of two international reviewers. W e wish to express our gratitude to all authors of papers and the international referee board. W e would also like to express our appreciation to the organising committee, chaired by Leon Strous, for aU their inputs and arrangements.

The current IT environment deals with novel, complex approaches such as information privacy, trust, digital forensics, management, and human aspects. This volume includes papers offering research contributions that focus both on access control in complex environments as well as other aspects of computer security and privacy.