Reducing Internet Latency : A Survey of Techniques and their Merit

Bob Briscoe, Anna Brunstrom, Andreas Petlund, David Hayes, David Ros, Ing-Jyh Tsang, Stein Gjessing, Gorry Fairhurst, Carsten Griwodz, Michael WelzlPeer reviewedPreprin

Using Software-Defined Networking and Openflow Switching to Reroute Network Traffic Dynamically Based on Traffic Volume Measurements

Traditional switching and routing have been very effective for network packet delivery but does create some constraints. for example, all packets from a given source to a given destination must always take the same path. Within a traditional Ethernet network, a tree topology must be used. Software-Defined Networking (SDN) has the potential to bypass this tree-topology limitation by placing the control of the switches and their forwarding tables under a central device called a controller. SDN also allows for sets of controllers. the controller can identify individual network flows and issue commands to the switches to, in effect, assign individual flows to specific paths. This allows different flows between the same source and destination to take different paths. in this project we use SDN to assign TCP connections to specific paths through a network. Different connections between the same pair of endpoints can be assigned different paths. Different directions of the same TCP connection (different TCP flows ) can be assigned different paths. Paths are chosen by the controller, with full knowledge of the network topology, so there is no need for restrictions on topological loops. Unlike with Ethernet link aggregation, our approach does not require that the propagation delays on different links are equal, or even are similar. Each TCP flow gets a single path, which eliminates link-related packet reordering. One application of this is to achieve static load balancing. We create a specific topology in which there are multiple trunk lines between two host clusters; we can then spread the traffic load between the two host clusters evenly over the trunk lines. We are also able to achieve dynamic load balancing by periodically reassigning the TCP flows to different paths through the trunk lines. This distributes the traffic evenly over the trunk lines. for this portion of the project we assumed that individual TCP connections were rate limited, with the rate varying with time, so we could measure the per-connection bandwidths and assume these values would remain in effect for a reasonable interval. We create the networks and switches using the Mininet emulation environment

MANETs: Internet Connectivity and Transport Protocols

A Mobile Ad hoc Network (MANET) is a collection of mobile nodes connected together over a wireless medium, which self-organize into an autonomous multi-hop wireless network. This kind of networks allows people and devices to seamlessly internetwork in areas with no pre-existing communication infrastructure, e.g., disaster recovery environments. Ad hoc networking is not a new concept, having been around in various forms for over 20 years. However, in the past only tactical networks followed the ad hoc networking paradigm. Recently, the introduction of new technologies such as IEEE 802.11, are moved the application field of MANETs to a more commercial field. These evolutions have been generating a renewed and growing interest in the research and development of MANETs. It is widely recognized that a prerequisite for the commercial penetration of the ad hoc networking technologies is the integration with existing wired/wireless infrastructure-based networks to provide an easy and transparent access to the Internet and its services. However, most of the existing solutions for enabling the interconnection between MANETs and the Internet are based on complex and inefficient mechanisms, as Mobile-IP and IP tunnelling. This thesis describes an alternative approach to build multi-hop and heterogeneous proactive ad hoc networks, which can be used as flexible and low-cost extensions of traditional wired LANs. The proposed architecture provides transparent global Internet connectivity and address autocofiguration capabilities to mobile nodes without requiring configuration changes in the pre-existing wired LAN, and relying on basic layer-2 functionalities. This thesis also includes an experimental evaluation of the proposed architecture and a comparison between this architecture with a well-known alternative NAT-based solution. The experimental outcomes confirm that the proposed technique ensures higher per-connection throughputs than the NAT-based solution. This thesis also examines the problems encountered by TCP over multi-hop ad hoc networks. Research on efficient transport protocols for ad hoc networks is one of the most active topics in the MANET community. Such a great interest is basically motivated by numerous observations showing that, in general, TCP is not able to efficiently deal with the unstable and very dynamic environment provided by multi-hop ad hoc networks. This is because some assumptions, in TCP design, are clearly inspired by the characteristics of wired networks dominant at the time when it was conceived. More specifically, TCP implicitly assumes that packet loss is almost always due to congestion phenomena causing buffer overflows at intermediate routers. Furthermore, it also assumes that nodes are static (i.e., they do not change their position over time). Unfortunately, these assumptions do not hold in MANETs, since in this kind of networks packet losses due to interference and link-layer contentions are largely predominant, and nodes may be mobile. The typical approach to solve these problems is patching TCP to fix its inefficiencies while preserving compatibility with the original protocol. This thesis explores a different approach. Specifically, this thesis presents a new transport protocol (TPA) designed from scratch, and address TCP interoperability at a late design stage. In this way, TPA can include all desired features in a neat and coherent way. This thesis also includes an experimental, as well as, a simulative evaluation of TPA, and a comparison between TCP and TPA performance (in terms of throughput, number of unnecessary transmissions and fairness). The presented analysis considers several of possible configurations of the protocols parameters, different routing protocols, and various networking scenarios. In all the cases taken into consideration TPA significantly outperforms TCP

ACO-BASED VELOCITY-AWARE HANDOVER SCHEME FOR SEAMLESS MOBILE COMMUNICATIONS

芝浦工業大学201

Security protocols suite for machine-to-machine systems

Nowadays, the great diffusion of advanced devices, such as smart-phones, has shown that there is a growing trend to rely on new technologies to generate and/or support progress; the society is clearly ready to trust on next-generation communication systems to face today’s concerns on economic and social fields. The reason for this sociological change is represented by the fact that the technologies have been open to all users, even if the latter do not necessarily have a specific knowledge in this field, and therefore the introduction of new user-friendly applications has now appeared as a business opportunity and a key factor to increase the general cohesion among all citizens. Within the actors of this technological evolution, wireless machine-to-machine (M2M) networks are becoming of great importance. These wireless networks are made up of interconnected low-power devices that are able to provide a great variety of services with little or even no user intervention. Examples of these services can be fleet management, fire detection, utilities consumption (water and energy distribution, etc.) or patients monitoring. However, since any arising technology goes together with its security threats, which have to be faced, further studies are necessary to secure wireless M2M technology. In this context, main threats are those related to attacks to the services availability and to the privacy of both the subscribers’ and the services providers’ data. Taking into account the often limited resources of the M2M devices at the hardware level, ensuring the availability and privacy requirements in the range of M2M applications while minimizing the waste of valuable resources is even more challenging. Based on the above facts, this Ph. D. thesis is aimed at providing efficient security solutions for wireless M2M networks that effectively reduce energy consumption of the network while not affecting the overall security services of the system. With this goal, we first propose a coherent taxonomy of M2M network that allows us to identify which security topics deserve special attention and which entities or specific services are particularly threatened. Second, we define an efficient, secure-data aggregation scheme that is able to increase the network lifetime by optimizing the energy consumption of the devices. Third, we propose a novel physical authenticator or frame checker that minimizes the communication costs in wireless channels and that successfully faces exhaustion attacks. Fourth, we study specific aspects of typical key management schemes to provide a novel protocol which ensures the distribution of secret keys for all the cryptographic methods used in this system. Fifth, we describe the collaboration with the WAVE2M community in order to define a proper frame format actually able to support the necessary security services, including the ones that we have already proposed; WAVE2M was funded to promote the global use of an emerging wireless communication technology for ultra-low and long-range services. And finally sixth, we provide with an accurate analysis of privacy solutions that actually fit M2M-networks services’ requirements. All the analyses along this thesis are corroborated by simulations that confirm significant improvements in terms of efficiency while supporting the necessary security requirements for M2M networks

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

Internet of Things From Hype to Reality

The Internet of Things (IoT) has gained significant mindshare, let alone attention, in academia and the industry especially over the past few years. The reasons behind this interest are the potential capabilities that IoT promises to offer. On the personal level, it paints a picture of a future world where all the things in our ambient environment are connected to the Internet and seamlessly communicate with each other to operate intelligently. The ultimate goal is to enable objects around us to efficiently sense our surroundings, inexpensively communicate, and ultimately create a better environment for us: one where everyday objects act based on what we need and like without explicit instructions