Investigating SRAM PUFs in large CPUs and GPUs

Physically unclonable functions (PUFs) provide data that can be used for cryptographic purposes: on the one hand randomness for the initialization of random-number generators; on the other hand individual fingerprints for unique identification of specific hardware components. However, today's off-the-shelf personal computers advertise randomness and individual fingerprints only in the form of additional or dedicated hardware. This paper introduces a new set of tools to investigate whether intrinsic PUFs can be found in PC components that are not advertised as containing PUFs. In particular, this paper investigates AMD64 CPU registers as potential PUF sources in the operating-system kernel, the bootloader, and the system BIOS; investigates the CPU cache in the early boot stages; and investigates shared memory on Nvidia GPUs. This investigation found non-random non-fingerprinting behavior in several components but revealed usable PUFs in Nvidia GPUs.Comment: 25 pages, 6 figures. Code in appendi

Living Apart Together in Europe

A couple of years ago Joschka Fischer, the German minister of Foreign Affairs articulated his European dream, calling for a specification of the 'Finalität', that is the ultimate goal of the process of European integration. It came at a moment that Europe is challenged by two conflicting developments - globalization and localization - labeled by Tom Courchene as 'glocalization' [Watts 1994]. The outcome of the process of European integration is still unclear, but will be in line with the striking characterization of Alexis de Tocqueville of the original idea of the American federation

Anleiherating und Bonitätsrisiko: eine empirische Untersuchung der Renditespreads am deutschen Markt

Die Arbeit ANLEIHERATING UND BONITÄTSRISIKO untersucht die Zusammenhänge zwischen dem Rating von Anleihen, dem Risiko dieser Anleihen sowie ihren Risikoprämien (Spreads). Dazu wird in einem ersten Schritt - auf analytischer Ebene - untersucht, wie Ratings vergeben werden und welchen Einschränkungen sie unterliegen. Die wichtigsten Einschränkungen für den Kapitalmarkt hinsichtlich der Ableitung von quantitativen Risikogrößen (Ausfallwahrscheinlichkeit und ggf. Ausfallschwere) sind: Ordinalität und Relativität der verwendeten Skalen; die Zeitverzögerungen bei Ratingänderungen; die Intransparenz, Subjektivität und Urteilsunabhängigkeit des Ratingverfahrens bzw. der Ratingagenturen; die Erstellung von auftragslosen Ratings; die mangelnde Vergleichbarkeit von Ratings (zeitlich, zwischen Emissionen und zwischen Agenturen); die fehlende Äquidistanz von Ratings; das Risiko fehlerhafter Ratings. In einem zweiten Schritt wird empirisch untersucht, in welcher Höhe vom Markt Spreads (Überrenditen gegenüber den als risikolos geltenden Bundesanleihen) - je nach Rating - für bestimmte Anleihen gefordert werden. Datenbasis sind Kupon-Anleihen (ohne Sonderrechte) des DM-Euromarktes mit täglichen Kursen im Zeitraum Januar 1990 bis Dezember 1995. Die Untersuchungen bestätigen die Relativität: Ratings definieren nur im langfristigen Durchschnitt die Renditeabstände zwischen den verschiedenen Klassen. Kurzfristige Veränderungen der Spreads hingegen hängen von Veränderungen des allgemeinen Zinsniveaus und dem Verlauf der Zinsstrukturkurve ab. Diese beiden Größen weisen dabei einen negativen Einfluß auf, d.h. Zinserhöhungen führen zu Verringerungen der Spreads. Grundsätzlich gilt dabei aber, dass diese Effekte umso stärker ausfallen, je geringer die Bonität der Anleihen ist. Zusätzlich hängen die Spreadänderungen auch (positiv) von Veränderungen der Spreads der jeweils anderen Klassen ab. Als mögliche Erklärungsansätze bieten sich für diese Beobachtung auch an, dass der Markt Schwankungen der erwarteten Ausfallwahrscheinlichkeiten antizipiert und/oder Veränderungen der allgemeinen Risikoeinstellung vorliegen

Androgens and androgen receptors in prostatic cancer

Our understanding of the testicular control of growth and functioning of the accessory sex glands began with an observation in the 18th century of John Hunter (1), who discovered in animals the endocrine dependency of the prostate. He demonstrated that castration in experimental animals causes a decrease in the volume of the prostate. White (2) reported in 1895 favourable results of "double" castration in men with hypertrophy of the prostate and one year later Cabot (3) proposed castration as treatment for an enlarged prostate in general. Differentiation between carcinoma and BPH was not done. The studies of Huggins and Hodges (4,5) in the early 1940's defined the regulatory role of the testes and testicular androgens in prostatic cancer. Their work placed the orchiectomy for treatment of prostatic cancer on a scientific basis and brought its general acceptation. Since then different forms of hormonal therapy have been used in all stages of prostatic cancer. Today, in the 80's, endocrine manipulation is generally accepted as first treatment in disseminated disease, although the impact of hormonal manipulation on patient survival (6,7) and the optimal timing of the initation of treatment are still controversial (8-10). After more than 45 years of investigation no single hormonal treatment has proven to be superior, so the conclusion of Scott in an overview (11) on hormonal therapy for prostatic cancer: "We have gone as far as we can go in the hormonal treatment of advanced prostatic cancer, and it is unlikely that further search will reveal a better treatment than castration- estrogen therapy", may still be valid. This statement, although seemingly definite, bears the challenge to develop modalities of treatment which are more effective than endocrine manipulations. As a part of future treatment it will be necessary to find methods that enable us to predict which patient will and which patient will not have a prolonged response to hormonal treatment. The estimation of nuclear androgen receptor (ARn) seemed promissing according to the findings of Trachtenberg and Walsh (12) and Ghanadian et al (13). The present thesis is aimed to contribute to this problem

Unmanned and uncontrolled: The commingling theory and the legality of unmanned aircraft system operations

In 2002 Australia became the first nation to promulgate certification standards for the commercial use of drones or unmanned aircraft systems (UAS). Since that time the Australian Civil Aviation Safety Authority (CASA) has played a key role both domestically and internationally through the International Civil Aviation Organization (ICAO) in assisting to develop technical guidance materials that will enable contracting states to develop UAS regulations. An arduous component of this task is the fact that all existing aircraft are capable of being unmanned. Moreover, given the unbounded nature of aircraft operations, UAS regulations necessarily require international harmonisation. But the objective of developing universal UAS standards is still far from being finalised while the accelerating pace of UAS technological development continues to challenge traditional regulatory regimes and legal systems throughout the world. This paper considers the broader legal issues associated with civilian UAS operations and their integration into unsegregated civilian airspace. The Australian UAS regulatory experience is examined with some unique constitutional limitations identified in relation to the application of the so-called ‘commingling theory’. It is contended that such limitations may render void existing UAS regulation in certain situations – many of which are related to the operation of small UAS and may have significant privacy implications. In particular this paper finds that the regulations purporting to control the operation of systems that are not capable of commingling with aircraft operating within navigable airspace are ultra vires and hence of no legal effect. In concluding this paper strongly asserts that if the commercial benefits attendant to UAS operations is to be fully realised then their risks to society must be controlled through domestic legislation that is harmonised and consistent with internationally agreed guidelines