34 resultados para High speed communication
Resumo:
Network neutrality is a growing policy controversy. Traffic management techniques affect not only high-speed, high-money content, but by extension all other content too. Internet regulators and users may tolerate much more discrimination in the interests of innovation. For instance, in the absence of regulatory oversight, ISPs could use Deep Packet Inspection (DPI) to block some content altogether, if they decide it is not to the benefit of ISPs, copyright holders, parents or the government. ISP blocking is currently widespread in controlling spam email, and in some countries in blocking sexually graphic illegal images. In 1999 this led to scrutiny of foreclosure of Instant Messaging and video and cable-telephony horizontal merger. Fourteen years later, there were in 2013 net neutrality laws implemented in Slovenia, the Netherlands, Chile and Finland, regulation in the United States and Canada , co-regulation in Norway, and self-regulation in Japan, the United Kingdom and many other European countries . Both Germany and France in mid-2013 debated new net neutrality legislation, and the European Commission announced on 11 September 2013 that it would aim to introduce legislation in early 2014. This paper analyses these legal developments, and in particular the difficulty in assessing reasonable traffic management and ‘specialized’ (i.e. unregulated) faster services in both EU and US law. It also assesses net neutrality law against the international legal norms for user privacy and freedom of expression
Resumo:
This paper analyzes Spanish infrastructure policy since the early 1700s: Road building in the eighteenth century, railway creation and expansion in the nineteenth, motorway expansion in the twentieth, and high speed rail development in the twenty-first. The analysis reveals a long-term pattern, in which infrastructure policy in Spain has been driven not by the requirements of commerce and economic activity, but rather by the desire to centralize transportation around the country’s political capital.
Resumo:
In this article, a new technique for grooming low-speed traffic demands into high-speed optical routes is proposed. This enhancement allows a transparent wavelength-routing switch (WRS) to aggregate traffic en route over existing optical routes without incurring expensive optical-electrical-optical (OEO) conversions. This implies that: a) an optical route may be considered as having more than one ingress node (all inline) and, b) traffic demands can partially use optical routes to reach their destination. The proposed optical routes are named "lighttours" since the traffic originating from different sources can be forwarded together in a single optical route, i.e., as taking a "tour" over different sources towards the same destination. The possibility of creating lighttours is the consequence of a novel WRS architecture proposed in this article, named "enhanced grooming" (G+). The ability to groom more traffic in the middle of a lighttour is achieved with the support of a simple optical device named lambda-monitor (previously introduced in the RingO project). In this article, we present the new WRS architecture and its advantages. To compare the advantages of lighttours with respect to classical lightpaths, an integer linear programming (ILP) model is proposed for the well-known multilayer problem: traffic grooming, routing and wavelength assignment The ILP model may be used for several objectives. However, this article focuses on two objectives: maximizing the network throughput, and minimizing the number of optical-electro-optical conversions used. Experiments show that G+ can route all the traffic using only half of the total OEO conversions needed by classical grooming. An heuristic is also proposed, aiming at achieving near optimal results in polynomial time
Resumo:
El golpeo de la bola a velocidades elevadas, es un factor determinante para el rendimiento en el tenis moderno. Durante los últimos 20 años se ha producido una gran evolución del juego y los cambios en el juego moderno se han traducido en el uso de poderosos servicios y golpes de fondo. Aunque la fuerza es una capacidad determinante desde la perspectiva de la condición física, ha habido poca investigación para fundamentar la eficacia de los programas de entrenamiento de fuerza para los jugadores de tenis. El objetivo de este estudio es realizar una revisión sobre los criterios básicos para dirigir correctamente el entrenamiento de la fuerza orientado a la mejora de la de la velocidad de golpeo de la pelota. Aunque las necesidades de fuerza dinámica máxima (FDM) en los golpeos son bajas, la literatura científica parece apuntar que unos adecuados niveles de FDM ejercen efectos positivos sobre el aumento de velocidad de golpeo en el tenis. La mejora y mantenimiento de esta manifestación de fuerza se busca a expensas de factores neurales. Los entrenamientos de fuerza útil deben utilizar medios que permitan ejecutar el gesto técnico, implicar las mismas cadenas musculares, rango de movimiento o velocidades de ejecución. En este sentido, se han propuesto la utilización de pelotas medicinales, mancuernas de peso ligero, gomas elásticas, máquinas multifuncionales de resistencia neumática o poleas.