51,947 research outputs found
Internet of Things-aided Smart Grid: Technologies, Architectures, Applications, Prototypes, and Future Research Directions
Traditional power grids are being transformed into Smart Grids (SGs) to
address the issues in existing power system due to uni-directional information
flow, energy wastage, growing energy demand, reliability and security. SGs
offer bi-directional energy flow between service providers and consumers,
involving power generation, transmission, distribution and utilization systems.
SGs employ various devices for the monitoring, analysis and control of the
grid, deployed at power plants, distribution centers and in consumers' premises
in a very large number. Hence, an SG requires connectivity, automation and the
tracking of such devices. This is achieved with the help of Internet of Things
(IoT). IoT helps SG systems to support various network functions throughout the
generation, transmission, distribution and consumption of energy by
incorporating IoT devices (such as sensors, actuators and smart meters), as
well as by providing the connectivity, automation and tracking for such
devices. In this paper, we provide a comprehensive survey on IoT-aided SG
systems, which includes the existing architectures, applications and prototypes
of IoT-aided SG systems. This survey also highlights the open issues,
challenges and future research directions for IoT-aided SG systems
Deliverable JRA1.1: Evaluation of current network control and management planes for multi-domain network infrastructure
This deliverable includes a compilation and evaluation of available control and management architectures and protocols applicable to a multilayer infrastructure in a multi-domain Virtual Network environment.The scope of this deliverable is mainly focused on the virtualisation of the resources within a network and at processing nodes. The virtualization of the FEDERICA infrastructure allows the provisioning of its available resources to users by means of FEDERICA slices. A slice is seen by the user as a real physical network under his/her domain, however it maps to a logical partition (a virtual instance) of the physical FEDERICA resources. A slice is built to exhibit to the highest degree all the principles applicable to a physical network (isolation, reproducibility, manageability, ...). Currently, there are no standard definitions available for network virtualization or its associated architectures. Therefore, this deliverable proposes the Virtual Network layer architecture and evaluates a set of Management- and Control Planes that can be used for the partitioning and virtualization of the FEDERICA network resources. This evaluation has been performed taking into account an initial set of FEDERICA requirements; a possible extension of the selected tools will be evaluated in future deliverables. The studies described in this deliverable define the virtual architecture of the FEDERICA infrastructure. During this activity, the need has been recognised to establish a new set of basic definitions (taxonomy) for the building blocks that compose the so-called slice, i.e. the virtual network instantiation (which is virtual with regard to the abstracted view made of the building blocks of the FEDERICA infrastructure) and its architectural plane representation. These definitions will be established as a common nomenclature for the FEDERICA project. Other important aspects when defining a new architecture are the user requirements. It is crucial that the resulting architecture fits the demands that users may have. Since this deliverable has been produced at the same time as the contact process with users, made by the project activities related to the Use Case definitions, JRA1 has proposed a set of basic Use Cases to be considered as starting point for its internal studies. When researchers want to experiment with their developments, they need not only network resources on their slices, but also a slice of the processing resources. These processing slice resources are understood as virtual machine instances that users can use to make them behave as software routers or end nodes, on which to download the software protocols or applications they have produced and want to assess in a realistic environment. Hence, this deliverable also studies the APIs of several virtual machine management software products in order to identify which best suits FEDERICAâs needs.Postprint (published version
SDN/NFV-enabled satellite communications networks: opportunities, scenarios and challenges
In the context of next generation 5G networks, the satellite industry is clearly committed to revisit and revamp the role of satellite communications. As major drivers in the evolution of (terrestrial) fixed and mobile networks, Software Defined Networking (SDN) and Network Function Virtualisation (NFV) technologies are also being positioned as central technology enablers towards improved and more flexible integration of satellite and terrestrial segments, providing satellite network further service innovation and business agility by advanced network resources management techniques. Through the analysis of scenarios and use cases, this paper provides a description of the benefits that SDN/NFV technologies can bring into satellite communications towards 5G. Three scenarios are presented and analysed to delineate different potential improvement areas pursued through the introduction of SDN/NFV technologies in the satellite ground segment domain. Within each scenario, a number of use cases are developed to gain further insight into specific capabilities and to identify the technical challenges stemming from them.Peer ReviewedPostprint (author's final draft
Towards Autonomic Service Provisioning Systems
This paper discusses our experience in building SPIRE, an autonomic system
for service provision. The architecture consists of a set of hosted Web
Services subject to QoS constraints, and a certain number of servers used to
run session-based traffic. Customers pay for having their jobs run, but require
in turn certain quality guarantees: there are different SLAs specifying charges
for running jobs and penalties for failing to meet promised performance
metrics. The system is driven by an utility function, aiming at optimizing the
average earned revenue per unit time. Demand and performance statistics are
collected, while traffic parameters are estimated in order to make dynamic
decisions concerning server allocation and admission control. Different utility
functions are introduced and a number of experiments aiming at testing their
performance are discussed. Results show that revenues can be dramatically
improved by imposing suitable conditions for accepting incoming traffic; the
proposed system performs well under different traffic settings, and it
successfully adapts to changes in the operating environment.Comment: 11 pages, 9 Figures,
http://www.wipo.int/pctdb/en/wo.jsp?WO=201002636
Adding Policy-based Control to Mobile Hosts Switching between Streaming Proxies
We add a simple policy-based control component to mobile hosts that enables them to control the continuous reception of live multimedia content (e.g. a TV broadcast) while they switch between different distributors of that content. Policy-based control provides a flexible means to automate the switching behavior of mobile hosts. The policies react to changes in the mobile host's environment (e.g. when a hotspot network appears) and determine when and how to invoke an earlier developed application-level protocol to discover the capabilities (e.g. supported encodings) of the content distributors and to execute the switches. The design of the control component is based on the IETF policy model, but extended and applied at the application-level instead of at the network-level. We implemented the system and deployed it in a small-scale test bed
SDN as Active Measurement Infrastructure
Active measurements are integral to the operation and management of networks,
and invaluable to supporting empirical network research. Unfortunately, it is
often cost-prohibitive and logistically difficult to widely deploy measurement
nodes, especially in the core. In this work, we consider the feasibility of
tightly integrating measurement within the infrastructure by using Software
Defined Networks (SDNs). We introduce "SDN as Active Measurement
Infrastructure" (SAAMI) to enable measurements to originate from any location
where SDN is deployed, removing the need for dedicated measurement nodes and
increasing vantage point diversity. We implement ping and traceroute using
SAAMI, as well as a proof-of-concept custom measurement protocol to demonstrate
the power and ease of SAAMI's open framework. Via a large-scale measurement
campaign using SDN switches as vantage points, we show that SAAMI is accurate,
scalable, and extensible
Towards alignment of architectural domains in security policy specifications
Large organizations need to align the security architecture across three different domains: access control, network layout and physical infrastructure. Security policy specification formalisms are usually dedicated to only one or two of these domains. Consequently, more than one policy has to be maintained, leading to alignment problems. Approaches from the area of model-driven security enable creating graphical models that span all three domains, but these models do not scale well in real-world scenarios with hundreds of applications and thousands of user roles. In this paper, we demonstrate the feasibility of aligning all three domains in a single enforceable security policy expressed in a Prolog-based formalism by using the Law Governed Interaction (LGI) framework. Our approach alleviates the limitations of policy formalisms that are domain-specific while helping to reach scalability by automatic enforcement provided by LGI
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