Privacy protocols

Security protocols enable secure communication over insecure channels. Privacy protocols enable private interactions over secure channels. Security protocols set up secure channels using cryptographic primitives. Privacy protocols set up private channels using secure channels. But just like some security protocols can be broken without breaking the underlying cryptography, some privacy protocols can be broken without breaking the underlying security. Such privacy attacks have been used to leverage e-commerce against targeted advertising from the outset; but their depth and scope became apparent only with the overwhelming advent of influence campaigns in politics. The blurred boundaries between privacy protocols and privacy attacks present a new challenge for protocol analysis. Covert channels turn out to be concealed not only below overt channels, but also above: subversions, and the level-below attacks are supplemented by sublimations and the level-above attacks.Comment: 38 pages, 6 figure

Enriching Discourse on Public Domains

Is there one public domain, or are there many public domains? The scholarly literature predominantly assumes there is only one, for references abound to “the public domain” in the singular. Yet, even a cursory review of this literature reveals that scholars sometimes define this term differently. So if there is only one public domain, but many definitions, perhaps one objective of scholarly discourse about the public domain should be to seek consensus on the one “true” definition.Professor James Boyle has provocatively suggested that there are many public domains, and has urged scholars to develop a rich vocabulary for distinguishing among them. He points out that the word “property” has multiple meanings, and discourse about property proceeds without confusion because legal professionals have learned to discern which meaning is intended from the textual context. Boyle urges intellectual property scholars to develop a similarly nuanced public domain vocabulary so that it will be possible to distinguish among its several meanings as well.This essay considers the potential benefits of accepting the existence of multiple public domains and ways in which discourse about public domains might be enriched thereby. Part II provides a synopsis of thirteen conceptions of the public domain found in the law review literature, explaining each, generally by reviewing the explication of it offered by its principal proponent or discoverer. Part III organizes the definitions by recognizing that they cluster around three main foci: 1) the legal status of information resources, 2) freedoms to use information resources, even if protected by IP rights, and 3) accessibility of information resources. Although it is common to think of information resources as either IP-protected or public domain, and as either publicly accessible or not, Part III shows that the public domain literature views these concepts not as binary opposites, but rather as points along a continuum. Part IV discusses the advantages and disadvantages of recognizing multiple public domains and recommends the use of adjectives to clarify discourse about the many public domains. The constitutional public domain, for instance, is distinct from the privatizable (although not yet, privatized) public domain. This Part differentiates among conceptions of public domains that should be accepted and those that perhaps should not. The principal advantage of recognizing multiple public domains is that it illuminates a range of important social values served by these domains and a plethora of strategies for preserving them and the values they serve

Complexity and Unwinding for Intransitive Noninterference

The paper considers several definitions of information flow security for intransitive policies from the point of view of the complexity of verifying whether a finite-state system is secure. The results are as follows. Checking (i) P-security (Goguen and Meseguer), (ii) IP-security (Haigh and Young), and (iii) TA-security (van der Meyden) are all in PTIME, while checking TO-security (van der Meyden) is undecidable, as is checking ITO-security (van der Meyden). The most important ingredients in the proofs of the PTIME upper bounds are new characterizations of the respective security notions, which also lead to new unwinding proof techniques that are shown to be sound and complete for these notions of security, and enable the algorithms to return simple counter-examples demonstrating insecurity. Our results for IP-security improve a previous doubly exponential bound of Hadj-Alouane et al

Enriching Discourse on Public Domains

Studying microvascular responses to iontophoresis of vasoconstricting drugs contributes to a better understanding of the regulatory mechanisms of cutaneous vessels, but measuring these responses with laser-Doppler flowmetry at basal blood flow conditions is technically challenging. This study aimed to investigate whether the measurement of cutaneous vasoconstrictor responses to noradrenaline (NA) and phenylephrine (PE), delivered by iontophoresis, is facilitated by predilatation of the microvascular bed using local heating. We used different drug delivery rates (100 s x 0.12 mA, 200 s x 0.06 mA, 300 s x 0.04 mA) to investigate whether predilatation affects the local drug dynamics by an increased removal of drugs from the skin. In a predilatated vascular bed, iontophoresis of NA and PE resulted in a significant decrease in perfusion from the thermal plateau (p andlt; 0.001). The decrease was 25-33%, depending on drug delivery rate. In unheated skin, a significant vasoconstriction was observed (p andlt; 0.001), with 17% and 14% decrease from baseline for NA and PE, respectively. These results indicate that predilatating the cutaneous vascular bed by local heating facilitates measurement of vasoconstriction with laser-Doppler flowmetry and does not seem to significantly affect the result by an increased removal of drugs from the skin.Original Publication: Joakim Henricson, Yashma Baiat and Folke Sjöberg, Local Heating as a Predilatation Method for Measurement of Vasoconstrictor Responses with Laser-Doppler Flowmetry, 2011, MICROCIRCULATION, (18), 3, 214-220. http://dx.doi.org/10.1111/j.1549-8719.2010.00079.x Copyright: Wiley http://eu.wiley.com/WileyCDA/Brand/id-35.html</p

Building Machines That Learn and Think Like People

Recent progress in artificial intelligence (AI) has renewed interest in building systems that learn and think like people. Many advances have come from using deep neural networks trained end-to-end in tasks such as object recognition, video games, and board games, achieving performance that equals or even beats humans in some respects. Despite their biological inspiration and performance achievements, these systems differ from human intelligence in crucial ways. We review progress in cognitive science suggesting that truly human-like learning and thinking machines will have to reach beyond current engineering trends in both what they learn, and how they learn it. Specifically, we argue that these machines should (a) build causal models of the world that support explanation and understanding, rather than merely solving pattern recognition problems; (b) ground learning in intuitive theories of physics and psychology, to support and enrich the knowledge that is learned; and (c) harness compositionality and learning-to-learn to rapidly acquire and generalize knowledge to new tasks and situations. We suggest concrete challenges and promising routes towards these goals that can combine the strengths of recent neural network advances with more structured cognitive models.Comment: In press at Behavioral and Brain Sciences. Open call for commentary proposals (until Nov. 22, 2016). https://www.cambridge.org/core/journals/behavioral-and-brain-sciences/information/calls-for-commentary/open-calls-for-commentar