Towards Loop-Free Forwarding of Anonymous Internet Datagrams that Enforce Provenance

The way in which addressing and forwarding are implemented in the Internet constitutes one of its biggest privacy and security challenges. The fact that source addresses in Internet datagrams cannot be trusted makes the IP Internet inherently vulnerable to DoS and DDoS attacks. The Internet forwarding plane is open to attacks to the privacy of datagram sources, because source addresses in Internet datagrams have global scope. The fact an Internet datagrams are forwarded based solely on the destination addresses stated in datagram headers and the next hops stored in the forwarding information bases (FIB) of relaying routers allows Internet datagrams to traverse loops, which wastes resources and leaves the Internet open to further attacks. We introduce PEAR (Provenance Enforcement through Addressing and Routing), a new approach for addressing and forwarding of Internet datagrams that enables anonymous forwarding of Internet datagrams, eliminates many of the existing DDoS attacks on the IP Internet, and prevents Internet datagrams from looping, even in the presence of routing-table loops.Comment: Proceedings of IEEE Globecom 2016, 4-8 December 2016, Washington, D.C., US

Coaliciones legislativas en un contexto de Partido dominante: El caso de la LVIII Legislatura en el Congreso del Estado de México

En el presente trabajo se revela la existencia de una coalición ganadora amplia en la lviii Legislatura del Congreso del Estado de México que encabeza el Partido Revolucionario Institucional ( pri ) e integran otros cuatro partidos: Partido Acción Nacional ( pan ), Partido de la Revolución Democrática ( prd ), Partido Verde Ecologista de México ( pvem ) y Nueva Alianza ( na ). El objetivo de esta coalición no es construir una mayoría sino dar legitimidad a las iniciativas votadas en el Congreso. También se describe la posición de cada uno de los partidos representados en el Congreso del Estado de México en cuanto a su votación a favor, votación en contra, abstenciones y ausencia en las votaciones. Esta coalición tiene la particularidad de que, a diferencia de la competitividad existente a nivel nacional, que se refleja en la alternancia, en el Estado de México el sistema de partido dominante ha retomado un nuevo punto de equilibrio

Making Name-Based Content Routing More Efficient than Link-State Routing

The Diffusive Name-based Routing Protocol (DNRP) is introduced for efficient name-based routing in information-centric networks (ICN). DNRP establishes and maintains multiple loop-free routes to the nearest instances of a name prefix using only distance information. DNRP eliminates the need for periodic updates, maintaining topology information, storing complete paths to content replicas, or knowing about all the sites storing replicas of named content. DNRP is suitable for large ICNs with large numbers of prefixes stored at multiple sites. It is shown that DNRP provides loop-free routes to content independently of the state of the topology and that it converges within a finite time to correct routes to name prefixes after arbitrary changes in the network topology or the placement of prefix instances. The result of simulation experiments illustrates that DNRP is more efficient than link-state routing approaches

Análisis del contenido argumentativo en un corpus de ensayos en inglés

El objetivo general del proyecto “Análisis del contenido argumentativo en un corpus de ensayos en inglés” como el título lo sugiere, analizar el contenido de los argumentos en el discurso mediante la comparación y contraste de ensayos escritos por los alumnos, para obtener un modelo de referencia en el contexto la argumentación. Para empezar a discutir un modelo argumentativo, es importante saber primero qué es un argumento. Van Dijk (1978) lo define como un diálogo persuasivo, cuyo objetivo es convencer al receptor de la credibilidad de la aseveración propuesta. Para ser consistente, todo argumento debe incluir enunciados aceptables, razonamientos válidos y un esquema argumentativo apropiado y correcto. Díaz (2009) identifica seis elementos, de los cuales tres son obligatorios y tres opcionales. Los obligatorios son: punto de vista o conclusión (P), fundamentación (F), y garante (G). Los opcionales, aunque no menos importantes, son: condicionamiento de la conclusión (Cd), concesión (K) y refutación (R).Como veremos, estos elementos provienen del análisis de las corrientes de la argumentación

A Light-Weight Forwarding Plane for Content-Centric Networks

We present CCN-DART, a more efficient forwarding approach for content-centric networking (CCN) than named data networking (NDN) that substitutes Pending Interest Tables (PIT) with Data Answer Routing Tables (DART) and uses a novel approach to eliminate forwarding loops. The forwarding state required at each router using CCN-DART consists of segments of the routes between consumers and content providers that traverse a content router, rather than the Interests that the router forwards towards content providers. Accordingly, the size of a DART is proportional to the number of routes used by Interests traversing a router, rather than the number of Interests traversing a router. We show that CCN-DART avoids forwarding loops by comparing distances to name prefixes reported by neighbors, even when routing loops exist. Results of simulation experiments comparing CCN-DART with NDN using the ndnSIM simulation tool show that CCN-DART incurs 10 to 20 times less storage overhead

Enabling Correct Interest Forwarding and Retransmissions in a Content Centric Network

We show that the mechanisms used in the name data networking (NDN) and the original content centric networking (CCN) architectures may not detect Interest loops, even if the network in which they operate is static and no faults occur. Furthermore, we show that no correct Interest forwarding strategy can be defined that allows Interest aggregation and attempts to detect Interest looping by identifying Interests uniquely. We introduce SIFAH (Strategy for Interest Forwarding and Aggregation with Hop-Counts), the first Interest forwarding strategy shown to be correct under any operational conditions of a content centric network. SIFAH operates by having forwarding information bases (FIBs) store the next hops and number of hops to named content, and by having each Interest state the name of the requested content and the hop count from the router forwarding an Interest to the content. We present the results of simulation experiments using the ndnSIM simulator comparing CCN and NDN with SIFAH. The results of these experiments illustrate the negative impact of undetected Interest looping when Interests are aggregated in CCN and NDN, and the performance advantages of using SIFAH

The use of Planetary Nebulae precursors in the study of Diffuse Interstellar Bands

We present the first results of a systematic search for Diffuse Interstellar Bands in a carefully selected sample of post-AGB stars observed with high resolution optical spectroscopy. These stars are shown to be ideal targets to study this old, intriguing astrophysical problem. Our results suggest that the carrier(s) of these bands may not be present in the circumstellar environments of these evolved stars. The implications of the results obtained on the identification of the still unknown carrier(s) are discussed.Comment: 4 pages, 2 figures, proceedings of the conference 'Planetary Nebulae as Astrophysical Tools', held in Gdansk, Poland (June 28 - July 2, 2005

Role of resonances in rho^0 -> pi^+ pi^- gamma

We study the effect of the sigma(600) and a_1(1260) resonances in the rho^0 -> pi^+ pi^- gamma decay, within the meson dominance model. Major effects are driven by the mass and width parameters of the sigma(600), and the usually neglected contribution of the a_1(1260), although small by itself, may become sizable through its interference with pion bremsstrahlung, and the proper relative sign can favor the central value of the experimental branching ratio. We present a procedure, using the gauge invariant structure of the resonant amplitudes, to kinematically enhance the resonant effects in the angular and energy distribution of the photon. We also elaborate on the coupling constants involved.Comment: 5 pages, 5 figures, accepted for publication in PR