Revisiting credit distribution algorithms for distributed termination detection

This paper revisits distributed termination detection algorithms in the context of High-Performance Computing (HPC) applications. We introduce an efficient variant of the Credit Distribution Algorithm (CDA) and compare it to the original algorithm (HCDA) as well as to its two primary competitors: the Four Counters algorithm (4C) and the Efficient Delay-Optimal Distributed algorithm (EDOD). We analyze the behavior of each algorithm for some simplified task-based kernels and show the superiority of CDA in terms of the number of control messages.Peer ReviewedPostprint (author's final draft

Revisiting Credit Distribution Algorithms for Distributed Termination Detection

International audienceThis paper revisits distributed termination detection algorithms in the context of High-Performance Computing (HPC) applications. We introduce an efficient variant of the Credit Distribution Algorithm (CDA) and compare it to the original algorithm (HCDA) as well as to its two primary competitors: the Four Counters algorithm (4C) and the Efficient Delay-Optimal Distributed algorithm (EDOD). We analyze the behavior of each algorithm for some simplified task-based kernels and show the superiority of CDA in terms of the number of control messages

Trust the Masked Stranger: Unveiling the African Stokvel\u27s Blockchain Enticement

Blockchain technologies offer platforming services on which African stokvels can be implemented. stokvels emerged as cooperative and self-help schemes for marginalized communities in South Africa. stokvel members contributing to a blockchain-managed common fund do not have to worry about trusting their peers because transactions on a blockchain are claimed to be transparent and irrefutable. Blockchain technology’s consensus mechanism and its decentralized architecture ensure that authority is shared amongst peers, and none has monopolistic powers over the common fund. The blockchain is thus, at face value, seen as espousing the true spirit of cooperative and participative decision-making akin to African Ubuntu - the value system behind the African stokvel. This article critically analyses the superimposition of blockchain technology on African values-driven systems such as the stokvel. The paper problematizes two assumptions that are often taken for granted - that blockchain technology espouses the values of Ubuntu and that its implementation as an enabling technology for self-help financial schemes such as the African stokvel enhances the values of Ubuntu. The paper contributes to the literature that evaluates the implementation of financial technologies, particularly, blockchain technology in managing the transactions of cooperative self-help schemes in an African setup. It is argued and concluded that blockchain technology, like most other technological innovations, brings with it the comforts of Western modernity, while eroding the core values of Ubuntu such as care, pity, and empathy which are the founding values of the African stokvels. The recommendation made to African societies is to be cautious when adopting and using financial technology platforms such as blockchains as they are incompatible with African norms and probably designed to serve the profiteering agendas of technopreneurs

Comparing Distributed Termination Detection Algorithms for Task-Based Runtime Systems on HPC platforms

International audienceThis paper revisits distributed termination detection algorithms in the context of High-Performance Computing (HPC) applications. We introduce an efficient variant of the Credit Distribution Algorithm (CDA) and compare it to the original algorithm (HCDA) as well as to its two primary competitors: the Four Counters algorithm (4C) and the Efficient Delay-Optimal Distributed algorithm (EDOD). We analyze the behavior of each algorithm for some simplified task-based kernels and show the superiority of CDA in terms of the number of control messages. We then compare the implementation of these algorithms over a task-based runtime system, PaRSEC and show the advantages and limitations of each approach on a practical implementation

The Anatomy of the Internet Meets the Body of the Law

Symposium: Copyright Owners\u27 Rights and Users\u27 Privileges on the Interne

Counselor Recovery Status and Substance Abuse Certification: A Relationship to Perceived Credibility and Counselor Preference with Hazardous Drinkers

This study investigated the role of counselor influence in substance abuse counseling. Hazardous drinkers\u27 perceptions of a counselor\u27s recovery and certification status were examined to determine if these counselor characteristics increased hazardous drinkers\u27 perceptions of counselor crediblity or their counselor preference. No statically significant relationship was found between counselor recovery status and ratings of counselor credibility. Contrary to what was hypothesized participants rated themselves as less willing to choose a counselor in recovery than one who did not report a recovery history. This finding, albeit an inverse relationship from what was hypothesized, adds to the group membership similarity literature in regard to participants\u27 perceptions of counselor recovery status. Although counselor certification in substance abuse has become more prevalent, there were no differences between certified and non-certified counselors on either dependent variable. This study did not find an interaction effect between counselor recovery status and certification status. Clinical implications for counselors working with substance abuse are discussed

Counselor Recovery Status and Substance Abuse Certification: A Relationship to Perceived Credibility and Counselor Preference with Hazardous Drinkers

This study investigated the role of counselor influence in substance abuse counseling. Hazardous drinkers\u27 perceptions of a counselor\u27s recovery and certification status were examined to determine if these counselor characteristics increased hazardous drinkers\u27 perceptions of counselor crediblity or their counselor preference. No statically significant relationship was found between counselor recovery status and ratings of counselor credibility. Contrary to what was hypothesized participants rated themselves as less willing to choose a counselor in recovery than one who did not report a recovery history. This finding, albeit an inverse relationship from what was hypothesized, adds to the group membership similarity literature in regard to participants\u27 perceptions of counselor recovery status. Although counselor certification in substance abuse has become more prevalent, there were no differences between certified and non-certified counselors on either dependent variable. This study did not find an interaction effect between counselor recovery status and certification status. Clinical implications for counselors working with substance abuse are discussed

Modeling Deception for Cyber Security

In the era of software-intensive, smart and connected systems, the growing power and so- phistication of cyber attacks poses increasing challenges to software security. The reactive posture of traditional security mechanisms, such as anti-virus and intrusion detection systems, has not been sufficient to combat a wide range of advanced persistent threats that currently jeopardize systems operation. To mitigate these extant threats, more ac- tive defensive approaches are necessary. Such approaches rely on the concept of actively hindering and deceiving attackers. Deceptive techniques allow for additional defense by thwarting attackers’ advances through the manipulation of their perceptions. Manipu- lation is achieved through the use of deceitful responses, feints, misdirection, and other falsehoods in a system. Of course, such deception mechanisms may result in side-effects that must be handled. Current methods for planning deception chiefly portray attempts to bridge military deception to cyber deception, providing only high-level instructions that largely ignore deception as part of the software security development life cycle. Con- sequently, little practical guidance is provided on how to engineering deception-based techniques for defense. This PhD thesis contributes with a systematic approach to specify and design cyber deception requirements, tactics, and strategies. This deception approach consists of (i) a multi-paradigm modeling for representing deception requirements, tac- tics, and strategies, (ii) a reference architecture to support the integration of deception strategies into system operation, and (iii) a method to guide engineers in deception mod- eling. A tool prototype, a case study, and an experimental evaluation show encouraging results for the application of the approach in practice. Finally, a conceptual coverage map- ping was developed to assess the expressivity of the deception modeling language created.Na era digital o crescente poder e sofisticação dos ataques cibernéticos apresenta constan- tes desafios para a segurança do software. A postura reativa dos mecanismos tradicionais de segurança, como os sistemas antivírus e de detecção de intrusão, não têm sido suficien- tes para combater a ampla gama de ameaças que comprometem a operação dos sistemas de software actuais. Para mitigar estas ameaças são necessárias abordagens ativas de defesa. Tais abordagens baseiam-se na ideia de adicionar mecanismos para enganar os adversários (do inglês deception). As técnicas de enganação (em português, "ato ou efeito de enganar, de induzir em erro; artimanha usada para iludir") contribuem para a defesa frustrando o avanço dos atacantes por manipulação das suas perceções. A manipula- ção é conseguida através de respostas enganadoras, de "fintas", ou indicações erróneas e outras falsidades adicionadas intencionalmente num sistema. É claro que esses meca- nismos de enganação podem resultar em efeitos colaterais que devem ser tratados. Os métodos atuais usados para enganar um atacante inspiram-se fundamentalmente nas técnicas da área militar, fornecendo apenas instruções de alto nível que ignoram, em grande parte, a enganação como parte do ciclo de vida do desenvolvimento de software seguro. Consequentemente, há poucas referências práticas em como gerar técnicas de defesa baseadas em enganação. Esta tese de doutoramento contribui com uma aborda- gem sistemática para especificar e desenhar requisitos, táticas e estratégias de enganação cibernéticas. Esta abordagem é composta por (i) uma modelação multi-paradigma para re- presentar requisitos, táticas e estratégias de enganação, (ii) uma arquitetura de referência para apoiar a integração de estratégias de enganação na operação dum sistema, e (iii) um método para orientar os engenheiros na modelação de enganação. Uma ferramenta protó- tipo, um estudo de caso e uma avaliação experimental mostram resultados encorajadores para a aplicação da abordagem na prática. Finalmente, a expressividade da linguagem de modelação de enganação é avaliada por um mapeamento de cobertura de conceitos