EMICOM: Enhanced Media Independent COnnection Manager

With the increasing amount of mobile interfaces combining different kinds of access technologies, ranging from Wi-Fi to 3G and LTE, the integration of flexible and mediaindependent link control mechanisms becomes of paramount importance. By employing an abstract way of obtaining access link status information and exercising control over the network interface operations, these control mechanisms become able to optimize device connectivity and network attachment. This paper presents EMICOM, an Enhanced Media Independent COnnection Manager framework where a GNU/Linux Network Manager and Link Service Access Points for the IEEE 802.3 and 802.11 technologies were implemented and integrated through crosslayer Media Independent Handover (MIH) mechanisms from the IEEE 802.21 standard. Through an open-source implementation of the framework, the (MIH) command set capabilities are extended, allowing the support of network association and authentication, as well as Layer 3 services such as IP configuration, providing a generic solution for optimal network connectivity management

Media independent transport service for ambient intelligence

The evolution on ambient intelligence technologies, such as sensor networks, propelled a universe of very diverse types of both data and hardware equipment creating one of the most heterogeneous network environments. This diversity brings to light the main issue we aim to address in this paper: the need for a common ground that enables communications between the different heterogeneous equipments and technologies. Starting from the well-established IEEE 802.21 Media Independent Handover standard, we propose its mechanisms and structure to be extended to provide the needed common ground for communication in ambient intelligence scenarios. In this work, we extend 802.21 to include sensor information, enabling different types of equipment and network technologies to communicate with each other under a common standard contributing to a truly heterogeneous network framework. To conclude, we address its viability through a comparison with other known solutions for communication on sensing devices

New concepts for traffic, resource and mobility management in software-defined mobile networks

The evolution of mobile telecommunication networks is accompanied by new demands for the performance, portability, elasticity, and energy efficiency of network functions. Network Function Virtualization (NFV), Software Defined Networking (SDN), and cloud service technologies are claimed to be able to provide most of the capabilities. However, great leap forward will only be achieved if resource, traffic, and mobility management methods of mobile network services can efficiently utilize these technologies. This paper conceptualizes the future requirements of mobile networks and proposes new concepts and solutions in the form of Software-Defined Mobile Networks (SDMN) leveraging SDN, NFV and cloud technologies. We evaluate the proposed solutions through testbed implementations and simulations. The results reveal that our proposed SDMN enhancements supports heterogeneity in wireless networks with performance improvements through programmable interfaces and centralized control

Sensor context information for energy-efficient optimization of wireless procedures

The wide deployment of Wireless Local Area Networks (WLAN) we are witnessing today increases connectivity opportunities for mobile terminal devices, such as smartphones. However, continuous scanning for WLAN points of attachment can be a power exhausting mechanism for such battery-powered devices. These mobile devices, besides being equipped with different wireless access interfaces, are also coupled with sensors such as accelerometer, GPS, luminance and magnetic compass. In fact, sensors are increasingly being coupled into different devices and environments and are able to convey sensing information through networks into decision entities able to optimize different processes. In this paper we propose a framework where media independent sensing information is used to enhance wireless link management towards energy-efficiency. This framework enables the dissemination of sensing information towards local and remote decision entities, enhancing other processes (e.g. mobility) with sensing information in order to provide true Ambient Intelligence scenarios. We introduce this framework into a wireless management scenario able to provide energy-efficient optimal network connectivity

Efficient access of mobile flows to heterogeneous networks under flash crowds

Future wireless networks need to offer orders of magnitude more capacity to address the predicted growth in mobile traffic demand. Operators to enhance the capacity of cellular networks are increasingly using WiFi to offload traffic from their core networks. This paper deals with the efficient and flexible management of a heterogeneous networking environment offering wireless access to multimode terminals. This wireless access is evaluated under disruptive usage scenarios, such as flash crowds, which can mean unwanted severe congestion on a specific operator network whilst the remaining available capacity from other access technologies is not being used. To address these issues, we propose a scalable network assisted distributed solution that is administered by centralized policies, and an embedded reputation system, by which initially selfish operators are encouraged to cooperate under the threat of churn. Our solution after detecting a congested technology, including within its wired backhaul, automatically offloads and balances the flows amongst the access resources from all the existing technologies, following some quality metrics. Our results show that the smart integration of access networks can yield an additional wireless quality for mobile flows up to thirty eight percent beyond that feasible from the best effort standalone operation of each wireless access technology. It is also evidenced that backhaul constraints are conveniently reflected on the way the flow access to wireless media is granted. Finally, we have analyzed the sensitivity of the handover decision algorithm running in each terminal agent to consecutive flash crowds, as well as its centralized feature that controls the connection quality offered by a heterogeneous access infrastructure owned by distinct operators

Interoperabilidade e mobilidade na internet do futuro

Research on Future Internet has been gaining traction in recent years, with both evolutionary (e.g., Software Defined Networking (SDN)- based architectures) and clean-slate network architectures (e.g., Information Centric Networking (ICN) architectures) being proposed. With each network architectural proposal aiming to provide better solutions for specific Internet utilization requirements, an heterogeneous Future Internet composed by several architectures can be expected, each targeting and optimizing different use case scenarios. Moreover, the increasing number of mobile devices, with increasing capabilities and supporting different connectivity technologies, are changing the patterns of traffic exchanged in the Internet. As such, this thesis focuses on the study of interoperability and mobility in Future Internet architectures, two key requirements that need to be addressed for the widely adoption of these network architectures. The first contribution of this thesis is an interoperability framework that, by enabling resources to be shared among different network architectures, avoids resources to be restricted to a given network architecture and, at the same time, promotes the initial roll out of new network architectures. The second contribution of this thesis consists on the development of enhancements for SDN-based and ICN network architectures through IEEE 802.21 mechanisms to facilitate and optimize the handover procedures on those architectures. The last contribution of this thesis is the definition of an inter-network architecture mobility framework that enables MNs to move across access network supporting different network architectures without losing the reachability to resources being accessed. All the proposed solutions were evaluated with results highlighting the feasibility of such solutions and the impact on the overall communication.A Internet do Futuro tem sido alvo de vários estudos nos últimos anos, com a proposta de arquitecturas de rede seguindo quer abordagens evolutionárias (por exemplo, Redes Definidas por Software (SDN)) quer abordagens disruptivas (por exemplo, Redes Centradas na Informação (ICN)). Cada uma destas arquitecturas de rede visa providenciar melhores soluções relativamente a determinados requisitos de utilização da Internet e, portanto, uma Internet do Futuro heterogénea composta por diversas arquitecturas de rede torna-se uma possibilidade, onde cada uma delas é usada para optimizar diferentes casos de utilização. Para além disso, o aumento do número de dispositivos móveis, com especificações acrescidas e com suporte para diferentes tecnologias de conectividade, está a mudar os padrões do tráfego na Internet. Assim, esta tese foca-se no estudo de aspectos de interoperabilidade e mobilidade em arquitecturas de rede da Internet do Futuro, dois importantes requisitos que necessitam de ser satisfeitos para que a adopção destas arquitecturas de rede seja considerada. A primeira contribuição desta tese é uma solução de interoperabilidade que, uma vez que permite que recursos possam ser partilhados por diferentes arquitecturas de rede, evita que os recursos estejam restringidos a uma determinada arquitectura de rede e, ao mesmo tempo, promove a adopção de novas arquitecturas de rede. A segunda contribuição desta tese consiste no desenvolvimento de extensões para arquitecturas de rede baseadas em SDN ou ICN através dos mecanismos propostos na norma IEEE 802.21 com o objectivo de facilitar e optimizar os processos de mobilidade nessas arquitecturas de rede. Finalmente, a terceira contribuição desta tese é a definição de uma solução de mobilidade envolvendo diferentes arquitecturas de rede que permite a mobilidade de dispositivos móveis entre redes de acesso que suportam diferentes arquitecturas de rede sem que estes percam o acesso aos recursos que estão a ser acedidos. Todas as soluções propostas foram avaliadas com os resultados a demonstrar a viabilidade de cada uma das soluções e o impacto que têm na comunicação.Programa Doutoral em Informátic