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

Chromatin regulators as capacitors of interspecies variations in gene expression

Deletion of eight chromatin regulators and one transcription factor increases the variability in gene expression between two closely related yeast species, suggesting that large-scale regulators often buffer variations in gene expression.Similar analysis of metabolic enzymes indicates that, unlike regulators, these enzymes do not buffer gene expression variations

What Happens When Mediation is Institutionalized?: To the Parties, Practitioners, and Host Institutions

The Alternative Dispute Resolution Section of the Association of American Law Schools presented a program, at the 1994 AALS Conference, on the institutionalization of mediation – through courtconnected programs and otherwise. The topic is an important one, because this phenomenon has become increasingly common in recent years. Moreover, the topic seemed especially appropriate for the 1994 program, since Florida – the host state for the conference – was one of the first states to adopt a comprehensive statute providing for court-ordered mediation (at the trial judge\u27s option) in civil disputes of all kinds. The move toward institutionalizing mediation has raised many questions, and this program was designed to highlight those questions, and provoke this discussion about them. The panel for the program was composed of mediation scholars, teachers and practitioners, from eight diverse jurisdictions around the country, with expertise on many different aspects of the institutionalization issue. The program was organized by Professor Baruch Bush (Program Chair), together with Professor Carol Liebman (Section Chair) and Dean James Alfini (Panel Moderator). This article presents an edited transcript of the panelists\u27 comments

What Happens When Mediation is Institutionalized?: To the Parties, Practitioners, and Host Institutions

The Alternative Dispute Resolution Section of the Association of American Law Schools presented a program, at the 1994 AALS Conference, on the institutionalization of mediation – through courtconnected programs and otherwise. The topic is an important one, because this phenomenon has become increasingly common in recent years. Moreover, the topic seemed especially appropriate for the 1994 program, since Florida – the host state for the conference – was one of the first states to adopt a comprehensive statute providing for court-ordered mediation (at the trial judge\u27s option) in civil disputes of all kinds. The move toward institutionalizing mediation has raised many questions, and this program was designed to highlight those questions, and provoke this discussion about them. The panel for the program was composed of mediation scholars, teachers and practitioners, from eight diverse jurisdictions around the country, with expertise on many different aspects of the institutionalization issue. The program was organized by Professor Baruch Bush (Program Chair), together with Professor Carol Liebman (Section Chair) and Dean James Alfini (Panel Moderator). This article presents an edited transcript of the panelists\u27 comments

Knowledge-defined networking

The research community has considered in the past the application of Artificial Intelligence (AI) techniques to control and operate networks. A notable example is the Knowledge Plane proposed by D.Clark et al. However, such techniques have not been extensively prototyped or deployed in the field yet. In this paper, we explore the reasons for the lack of adoption and posit that the rise of two recent paradigms: Software-Defined Networking (SDN) and Network Analytics (NA), will facilitate the adoption of AI techniques in the context of network operation and control. We describe a new paradigm that accommodates and exploits SDN, NA and AI, and provide use-cases that illustrate its applicability and benefits. We also present simple experimental results that support, for some relevant use-cases, its feasibility. We refer to this new paradigm as Knowledge-Defined Networking (KDN).Peer ReviewedPostprint (author's final draft

Excavations in the Acheulean Levels at the Earlier Stone Age site of Canteen Koppie, Northern Province, South Africa

The fluvial gravels of the river Vaal in South Africa have long been known as a source for Earlier Stone Age (ESA) artefacts. Most were discovered through the open cast mining for diamonds that has left very little in situ fluvial sediment remaining today. The site of Canteen Koppie is an internationally famous location with a reputation for prolific Acheulean artefacts, especially handaxes and the enigmatic prepared core and Levallois-like technology known as Victoria West. Our understanding of this site, and most other Vaal locations, is almost solely based on highly selected artefact collections. Here, we report on the first controlled excavations ever to be conducted at Canteen Koppie. The deposits are likely to date to the Early and Middle Pleistocene, and our excavations sample the full depth of the stratigraphic sequence. The lower units, first identified in these excavations, add a considerable time depth to the Acheulean occupation of the site, making this the longest chrono-stratigraphic sequence in South Africa to our knowledge. Given the current international interest in the origins of Levallois/prepared core technology (PCT), its occurrence in Unit 2b Upper, and its presence alongside Victoria West technology in Unit 2a has significant implications for debates on the role of Victoria West in the origins of PCT. From the Canteen Koppie evidence, Levallois and Victoria West are clearly rooted in the Acheulean.RésuméOn sait depuis longtemps que les graviers fluviaux de la rivière Vaal en Afrique du Sud sont une source d'artefacts de l'âge de pierre ancien (ESA). Ils ont été découverts pour la plupart au cours de l'extraction de diamants dans des mines à ciel ouvert, ce qui fait qu'il ne reste que très peu de sédiments fluviaux in situ aujourd'hui. Le site de Canteen Koppie est un lieu célèbre dans le monde entier, réputé pour l'abondance de ses artefacts acheuléens, en particulier les bifaces et la technologie enigmatique des nucléus préparés semblable au Levallois connue sous le nom de Victoria West. Notre compréhension de ce site, et de la plupart des autres lieux du Vaal, repose presque uniquement sur des collections d'artefacts extrèmement sélectionnés. Ici, nous faisons le compte rendu des premières fouilles contrôlées jamais menées à Canteen Koppie. Les dépôts datent probablement du début et du milieu du pléistocène et nos excavations prennent des échantillons de l'ensemble de la profondeur de la séquence stratigraphique. Les unités les plus basses, identifiées pour la première fois au cours de ces fouilles, ajoutent une profondeur temporelle considérable à l'occupation acheuléenne du site, elles en font la plus longue séquence chronostratigraphique d'Afrique du Sud à notre connaissance. Etant donné l'actuel intérêt international pour les origines de la technologie Levallois/nucléus préparé (PCT), sa rencontre dans l'Unité 2b Supérieure, et sa présence à côté de la technologie Victoria West dans l'Unité 2a ont d'importantes implications pour les débats sur le rôle de Victoria West dans les origines de PCT. D'après les témoignages de Canteen Koppie,il est clair que Levallois et Victoria West ont leurs racines dans l'acheuléen.ZusammenfassungDie Schwemmkiese des Flusses Vaal in Südafrika sind seit langem als Fundort altsteinzeitlicher Artefakte bekannt. Meist wurden sie während des Diamanttagebaus gefunden, durch den heute sehr wenige Sedimente noch in situ erhalten sind. Der Fundplatz Canteen Koppie ist ein international weithin bekannter Ort, der berühmt ist für reiche Artefakte des Acheuléen, insbesondere Faustkeile und die rätselhafte, an Levallois erinnernde Kerntechnologie, die als Victoria West bekannt ist. Unser Verständnis dieses Fundplatzes, wie auch der meisten anderen Orte entlang des Vaal, basiert fast ausschließlich auf einer eng begrenzten Auswahl von Artefaktensembles. Hier berichten wir über die erste systematische Ausgrabung, die je in Canteen Koppie durchgeführt wurde. Die Schichten datieren wahrscheinlich ins Früh- und Mittelpleistozän; unsere Grabungen erfassten die gesamte Ausdehnung der stratigraphischen Abfolge. Die unteren Einheiten, die zuerst in den Grabungen identifiziert werden konnten, vergrößern die zeitliche Tiefe der Acheuléen-zeitlichen Nutzung des Ortes erheblich, wodurch dies nach unserem Wissen die längste chrono-stratigraphische Sequenz in Südafrika ist. Aufgrund des gegenwärtigen Interesses an den Ursprüngen der Levallois-Technik bzw. Technik der vorbereiteten Kerne (prepared core technology, PCT) ist ihr Auftreten in Unit 2b Upper und das Vorhandensein in Unit 2a, gemeinsam mit Victoria West-Technologie, von besonderer Bedeutung für die Diskussionen über die Rolle, die Victoria West bei der Entstehung von PCT spielt. Anhand der Beobachtungen in Canteen Koppie können wir festhalten, dass Levallois und Victoria West sicher im Acheuléen wurzeln.RésuménLas gravas fluviales del Rio Vaal en Sudáfrica han sido conocidas desde antiguo como una fuente de artefactos de la Primera Edad de Piedra (ESA en su acrónimo inglés). La mayoría han sido descubiertos al buscar diamantes al aire libre que ha dejado muy pocos sedientos fluviales in situ hoy en día. El yacimiento de Canteen Koppie es un emplazamiento internacionalmente famoso con una reputación de ser especialmente prolijo en artefactos del Achelense, especialmente hachas de mano y los enigmáticos núcleos preparados y la tecnología de estilo Levallois conocida como ‘Victoria West’. Nuestra comprensión de este yacimiento, y de la mayoría de los otros yacimientos en el Vaal, se basa casi exclusivamente en una serie de colecciones de artefactos altamente seleccionados. Este trabajo informa sobre las primeras excavaciones controladas jamás realizadas en Canteen Koppie. Los depósitos datan más probablemente al Pleistoceno Alto y Medio, y nuestra excavación cató toda la profundidad de la secuencia estratigráfica. Las capas más bajas, identificadas por primera vez en esta excavación, añaden una considerable profundidad temporal a la ocupación Achelense del yacimiento, y lo convierten, que sepamos, en la secuencia crono-estratigráfica más larga de Sudáfrica. Dado el interés internacional actual en los orígenes de la tecnología Levallois/núcleos preparados (PCT en su acrónimo inglés), su aparición en el Nivel 2b Superior, y su presencia junto con la tecnología Victoria West en el Nivel 2a tiene significativas consecuencias para los debates sobre el papel de Victoria West en los orígenes del PCT. Por lo que indica la evidencia de Canteen Koppie, las tecnologías Levallois y Victoria West están ambas claramente enraizadas en el Achelense

Life without the Movius Line: The structure of the East and Southeast Asian Early Palaeolithic

© 2015 Elsevier Ltd and INQUA.The starting point of this paper is that the Movius Line is no longer an appropriate way of studying the Early Palaeolithic of East and Southeast Asia, and should be disregarded. Instead, it is argued that the Early Palaeolithic of East and Southeast Asia needs to be seen as comparable to that in the rest of Eurasia, rather than the product of an isolated backwater. Contra Movius, East Asia was not isolated throughout the entire Early and Middle Pleistocene, but open to immigration during interglacials, as is indicated by its fossil hominin record. As in Europe and Southwest Asia, both bifacial and non-biface assemblages are present in China and Korea, thus indicating the presence of an Acheulean component, although the lack of agreement over how the Acheulean should be defined creates difficulties in establishing its extent in Southeast Asia. Regarding non-biface assemblages, Zhoukoudian was an unfortunate choice of an East Asian site that lacked bifaces, as bifaces are also rare or absent in a number of caves in Southwest Asia and Europe. Additionally, the absence of bifaces in some sites is not convincingly demonstrated because of the small size of the lithic assemblage. Finally, the simple flake industries in Southeast Asia are likely contemporary with Upper Pleistocene, Middle Palaeolithic and microlithic assemblages in India rather than with Middle Pleistocene, Acheulean assemblages, as proposed by Movius