Global state, local decisions: Decentralized NFV for ISPs via enhanced SDN

The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.Peer ReviewedPostprint (author's final draft

Land/Homeland, Story/History: the social landscapes of the Southern Levant from Alexander to Augustus

This material has been published in revised form in The Social Archaeology of the Levant from Prehistory to the Present edited by Assaf Yasur-Landau, Eric H. Cline, and Yorke Rowan https://doi.org/10.1017/9781316661468.024. This version is free to view and download for private research and study only. Not for re-distribution or re-use. © Cambridge University PressThe Hellenistic era opens with Alexander the Great’s triumph over Achaemenid Persia, an event that inaugurates a millennium of western political hegemony over the Levant and paves the way for an infusion of western cultural ideas. I examine the social repercussions of this juncture of politics and culture for five self-identifying ethnoi within the region: Phoenicians (meaning Tyrians and Sidonians), Samaritans, Judeans, Idumeans, and Nabateans. I consider physical and written evidence as reflections of agency, opportunity, status, and authority, in order to reconstruct how people defined and presented themselves, and how they jockeyed for position and security in a crowded region and a volatile world. Fortunes fluctuated along with changes in imperial rule. The Ptolemies instituted a rapacious system of resource extraction, under which only the most nimble or removed kept their footing (i.e., Phoenicians, Nabateans). The Seleucids followed in the more magnanimous footsteps of the Achaemenids, offering a measure of economic and legal autonomy, an approach that placated some (e.g., Samaritans) and empowered others (e.g., Judeans). As Seleucid control weakened, groups used various means to claim status and authority. Samaritans, Judeans, and Idumeans deployed history and geography; Phoenicians and Nabateans depended on economic connections and cultural currency. Waning imperial powers in the later second century BCE left the region’s ethnoi effectively autonomous. Phoenicians and Nabateans became wealthy cosmopolitans connected to Mediterranean markets. Judeans unleashed an aggressive program of territorial acquisition, first successfully against Idumeans and Samaritans, then less so against Tyrians and Nabateans. Contemporary writers turned these events into historical narratives – divinely countenanced (1 Maccabees, Dead Sea Scrolls) vs. opportunistic circumstance (2 Maccabees, Tacitus, Josephus). These accounts offered people differing templates by which to situate themselves in place and history – templates ill-suited for co-existence. By the time Roman authorities established their imperial presence here in the mid-first century BCE, the social landscape was mined and ready to erupt.Accepted manuscrip

Isolation of Anti-Ricin Protective Antibodies Exhibiting High Affinity from Immunized Non-Human Primates

Ricin, derived from the castor bean plant Ricinus communis, is one of the most potent and lethal toxins known, against which there is no available antidote. To date, the use of neutralizing antibodies is the most promising post-exposure treatment for ricin intoxication. The aim of this study was to isolate high affinity anti-ricin antibodies that possess potent toxin-neutralization capabilities. Two non-human primates were immunized with either a ricin-holotoxin- or subunit-based vaccine, to ensure the elicitation of diverse high affinity antibodies. By using a comprehensive set of primers, immune scFv phage-displayed libraries were constructed and panned. A panel of 10 antibodies (five directed against the A subunit of ricin and five against the B subunit) was isolated and reformatted into a full-length chimeric IgG. All of these antibodies were found to neutralize ricin in vitro, and several conferred full protection to ricin-intoxicated mice when given six hours after exposure. Six antibodies were found to possess exceptionally high affinity toward the toxin, with KD values below pM (koff < 1 × 10−7 s−1) that were well correlated with their ability to neutralize ricin. These antibodies, alone or in combination, could be used for the development of a highly-effective therapeutic preparation for post-exposure treatment of ricin intoxication

Global state, local decisions: Decentralized NFV for ISPs via enhanced SDN

The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.Peer Reviewe

Peak morphological diversity in an ecotone unveiled in the chukar partridge by a novel Estimator in a Dependent Sample (EDS)

1. Areas of environmental transition (i.e. ecotones) have recently been shown to play an important role in the maintenance of genetic diversity, divergence and in speciation processes. We test the hypothesis that ecotone populations maintain high phenotypic diversity compared to other populations across the distribution range