EmLog:Tamper-Resistant System Logging for Constrained Devices with TEEs

Remote mobile and embedded devices are used to deliver increasingly impactful services, such as medical rehabilitation and assistive technologies. Secure system logging is beneficial in these scenarios to aid audit and forensic investigations particularly if devices bring harm to end-users. Logs should be tamper-resistant in storage, during execution, and when retrieved by a trusted remote verifier. In recent years, Trusted Execution Environments (TEEs) have emerged as the go-to root of trust on constrained devices for isolated execution of sensitive applications. Existing TEE-based logging systems, however, focus largely on protecting server-side logs and offer little protection to constrained source devices. In this paper, we introduce EmLog -- a tamper-resistant logging system for constrained devices using the GlobalPlatform TEE. EmLog provides protection against complex software adversaries and offers several additional security properties over past schemes. The system is evaluated across three log datasets using an off-the-shelf ARM development board running an open-source, GlobalPlatform-compliant TEE. On average, EmLog runs with low run-time memory overhead (1MB heap and stack), 430--625 logs/second throughput, and five-times persistent storage overhead versus unprotected logs.Comment: Accepted at the 11th IFIP International Conference on Information Security Theory and Practice (WISTP '17

Deafening silence? Marxism, international historical sociology and the spectre of Eurocentrism

Approaching the centenary of its establishment as a formal discipline, International Relations today challenges the ahistorical and aspatial frameworks advanced by the theories of earlier luminaries. Yet, despite a burgeoning body of literature built on the transdisciplinary efforts bridging International Relations and its long-separated nomothetic relatives, the new and emerging conceptual frameworks have not been able to effectively overcome the challenge posed by the ‘non-West’. The recent wave of international historical sociology has highlighted possible trajectories to problematise the myopic and unipolar conceptions of the international system; however, the question of Eurocentrism still lingers in the developing research programmes. This article interjects into the ongoing historical materialist debate in international historical sociology by: (1) conceptually and empirically challenging the rigid boundaries of the extant approaches; and (2) critically assessing the postulations of recent theorising on ‘the international’, capitalist states-system/geopolitics and uneven and combined development. While the significance of the present contributions in international historical sociology should not be understated, it is argued that the ‘Eurocentric cage’ still occupies a dominant ontological position which essentially silences ‘connected histories’ and conceals the role of inter-societal relations in the making of the modern states-system and capitalist geopolitics

Salmonella Strains Isolated from Galápagos Iguanas Show Spatial Structuring of Serovar and Genomic Diversity

It is thought that dispersal limitation primarily structures host-associated bacterial populations because host distributions inherently limit transmission opportunities. However, enteric bacteria may disperse great distances during food-borne outbreaks. It is unclear if such rapid long-distance dispersal events happen regularly in natural systems or if these events represent an anthropogenic exception. We characterized Salmonella enterica isolates from the feces of free-living Galápagos land and marine iguanas from five sites on four islands using serotyping and genomic fingerprinting. Each site hosted unique and nearly exclusive serovar assemblages. Genomic fingerprint analysis offered a more complex model of S. enterica biogeography, with evidence of both unique strain pools and of spatial population structuring along a geographic gradient. These findings suggest that even relatively generalist enteric bacteria may be strongly dispersal limited in a natural system with strong barriers, such as oceanic divides. Yet, these differing results seen on two typing methods also suggests that genomic variation is less dispersal limited, allowing for different ecological processes to shape biogeographical patterns of the core and flexible portions of this bacterial species' genome

Análisis bibliométrico de la producción científica sobre cadena de valor turística

Para desarrollar el potencial turístico de una comunidad local, región o destino turístico en general es importante identificar cada uno de los elementos que lo componen y como es que éstos trabajan. Esta información es recabada y publicada, en su mayoría, en artículos científicos. Por lo que el objetivo central de esta investigación es analizar el estado del conocimiento, mediante un estudio bibliométrico retrospectivo, la producción científica que desarrolle mencione y proponga elementos relacionados con el tema cadenas de valor con enfoque turístico destacando factores como autor, afiliación, país, tipo de documento, entre otros. La metodología de la investigación se basa en una revisión documental e información bibliométrica retrospectiva de artículos relacionados con el tema de cadenas de valor turísticas. Para ello, se consultó la base de datos Scopus haciendo la búsqueda del tema ‘tourism value chain’ escrita en el título, resumen o palabras clave del artículo, teniendo como resultado 52 trabajos de investigación realizados entre los años 2010-2020. La consulta de dichos documentos se realizó entre el 20 de julio 2020 al 25 de junio de 2021 en el sitio web www.scopus.com. Se concluye que los estudios sobre cadenas de valor turísticas de los últimos diez años son pocas, en donde predomina la modalidad de artículo y como país líder Tailandia, aunque también hay países Latinoamericanos que pueden sentar las bases de este tema y visibilizar la importancia de la investigación de cadenas de valor turísticas para lograr un desarrollo equitativo entre todos los eslabones de la cadena.</jats:p