Abstract

The Call Admission Control (CAC) method presented in this paper is based on the statistical properties of the network’s traffic variables. It probabilistically estimates the time until the release of a seized channel: the admission control depends on the computed mean remaining time averaged along all channels at a specific instant and on a time threshold. The policy produces a smooth transition between the QoS metrics, giving the operator the freedom to design the network at the desired QoS point. Another valuable property is that the algorithm is straightforward and fed only by simple teletraffic metrics: distribution and the first and second moments of Channel Holding Time (CHT). Simplicity is important for a CAC method because decisions for accepting or rejecting calls must be computed quickly and frequently.

Abstract

Satellite Communications in the 5G Era explores promising scenarios for 5G Satellite Communications (SatCom), novel paradigms for satellite-terrestrial integration and emerging technologies for the next generation of satellite systems and hybrid/integrated satellite-terrestrial systems, and focuses on recent research efforts towards 5G and beyond. Satellite communications plays a vital role in ensuring seamless access to any telecommunications service anytime and anywhere, and is only a viable option for delivering telecommunication services in a wide range of sectors such as aeronautical, military, maritime, rescue and disaster relief. It should be an important component of 5G-and-beyond wireless architectures as it complements terrestrial telecommunication solutions in various scenarios and will ensure the expansion of the 5G ecosystem towards highly reliable and secure global wireless networks.

Abstract

[ANGLÈS]Lately, the emerging paradigm of Software-Defined Networking has grown in presence and claims to simplify future networking. The decoupling of network control and forwarding plane proposed by this architecture allows the control of the entire network behavior by means of a logically centralized software program (controller). Such separation of planes opens the way to Network Virtualization, which provides users a logical abstraction of underlying network resources. However, network virtualization requires a mapping phase of the virtual resources over the physical resources, which is not trivial, formally known as the virtual network embedding problem. The present document focuses in the development of a variant of one of the proposed strategies to solve this critical step, prioritizing the real-time response. The proposed algorithm uses the properties offered by the Paths Algebra mathematical framework to provide a flexible environment where it is possible to combine any number of both linear and non-linear metrics. In addition, it is also used the multi-lexical ordination, a criterion to better distinguish paths that may be considered equal by other approaches. Such algorithm has been implemented as a software application that provides a simulation environment where the virtual network embedding process can be tested for any given topology. Subsequently, all the algorithm features have been checked in a set of performance tests, focusing on those oriented to the commitment among the real-time response and the quality of the embedding solutions. In general, testing results are very promising even in densely populated backbone topologies, where the number of alternative paths among each possible pair of origin and destination nodes grows exponentially. [CASTELLÀ] Software-Defined Networking (o Redes Definidas por Software) es un nuevo paradigma que tiene como objetivo simplificar la creación y gestión de redes de ordenadores. El desacoplamiento entre el control de la red y el plano de reenvío propuesto por esta arquitectura permite el control de todo el comportamiento de la red mediante un elemento lógico centralizado, llamado controlador. Esta separación de los planos abre la puerta a la virtualización de redes, proporcionando a los usuarios una abstracción lógica de los recursos de red subyacentes. Sin embargo, la virtualización de red requiere de una fase de asignación de los recursos virtuales a los recursos físicos, que no es trivial y que se conoce formalmente como el problema de incrustación de redes virtuales. El presente documento se centra en el desarrollo de una variante de una de las estrategias propuestas para resolver este paso crítico, dando prioridad a la respuesta en tiempo real. El algoritmo propuesto utiliza las propiedades ofrecidas por el marco matemático de Paths Algebra (o Álgebra de Caminos) para proporcionar un entorno flexible donde es posible combinar cualquier número de métricas lineales y no lineales. Además, también utiliza la ordenación multi-léxica, un criterio para distinguir mejor aquellos caminos que podrían ser considerados equivalentes por otros enfoques. Este algoritmo se ha implementado como una aplicación de software que proporciona un entorno de simulación en el que se puede probar el proceso de incrustación de redes virtuales para cualquier topología. Posteriormente, se han comprobado todas las características del algoritmo mediante un conjunto de pruebas de rendimiento, priorizando aquellas orientadas al compromiso entre la respuesta en tiempo real y la calidad de las soluciones de incrustación. En general, los resultados de las pruebas son muy prometedores incluso en topologías de redes troncales densamente pobladas, donde el número de caminos alternativos entre cada posible nodo origen y destino crece exponencialmente.

Abstract

© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Resilience and high availability are considered as essential requirements in 5G networks. To fullfil these requirements, the integration of a satellite component within mobile backhaul networks arises as a compelling proposition to provide backup connectivity to critical cell sites and divert traffic from congested areas so that a limited capacity in their terrestrial links could be supplemented during peak-time or even replaced in case of total/partial failure or maintenance. This is especially of interest for public protection and disaster relief (PPDR) communications in remote/rural areas that might require the fast deployment of nework capacity as well as in distressed areas where the terrestrial backhaul infrastructure might have suffered damages. This paper first describes an architectural framework that enables the integration and management of the satellite capacity as a constituent part of a Software Defined Networking (SDN) -based traffic engineered mobile backhaul network. Then, a SDN-based Traffic Engineering (TE) application is proposed to manage some amount of dynamically steerable satellite capacity provisioned for resilience purposes to maximize a network utility function under both failure and nonfailure conditions in the terrestrial links. Numerical results are presented to assess the benefits of the proposed TE application and its performance is compared to that of a traditional overflow solution. Peer Reviewed

Abstract

This paper discusses some challenges that user mobility imposes over the user-centric protection model against security threats. This model is based on the idea of offloading the security applications from the end user device, and placing them in a trusted network node at the network's edge. Our research perspective is particularly centered around three interrelated mobility challenges, i) the allocation of the security applications “close” to the user, i.e., on network nodes with enhanced processing capabilities, ii) seamless mobility with negligible disruption of ongoing network connections, and iii) dynamic orchestration and management with support of security applications migration. Based on our arguments, we expose the main requirements and trade-offs to be considered in the attempt to support mobility in such environment. We propose a flexible solution that leverages Software Defined Networking, Network Function Virtualization and Computing at the Network Edge to offer a seamless on-path security protection to mobile users. Our preliminary experiments' results considering a WiFi mobile user show that seamless security migration and mobility are feasible in a simple real scenario. Vertical mobility and more complex use cases scenarios are envisioned for future research. Peer Reviewed Document type: Conference object