83 research outputs found

    An MDE Approach for Domain based Architectural Components Modelling.

    Get PDF
    International audienceComponent Based Software Engineering (CBSE) is a popular and widely adopted software engineering paradigm that has proven his usefulness and success to increase reusability and efficiency in various application domains. In this paper, we propose a common metamodel of a component to support all the requirements of CBSE taking into account the specificities of each domain. The resulting modeling framework serves primarily to capture the basic concepts of concerns related to component systems development based on the clear separation between the development process, interactions and the domain knowledge. As a proof of concept, we are evaluating the feasibility of our approach through the CCM component model applied to an use case for building systems having real-time requirements

    Container-based network function virtualization for software-defined networks

    Get PDF
    Today's enterprise networks almost ubiquitously deploy middlebox services to improve in-network security and performance. Although virtualization of middleboxes attracts a significant attention, studies show that such implementations are still proprietary and deployed in a static manner at the boundaries of organisations, hindering open innovation. In this paper, we present an open framework to create, deploy and manage virtual network functions (NF)s in OpenFlow-enabled networks. We exploit container-based NFs to achieve low performance overhead, fast deployment and high reusability missing from today's NFV deployments. Through an SDN northbound API, NFs can be instantiated, traffic can be steered through the desired policy chain and applications can raise notifications. We demonstrate the systems operation through the development of exemplar NFs from common Operating System utility binaries, and we show that container-based NFV improves function instantiation time by up to 68% over existing hypervisor-based alternatives, and scales to one hundred co-located NFs while incurring sub-millisecond latency

    A Survey on Quality of Service in the Voice Over IP Technology

    Get PDF
    Voice services can be transmitted by circuit switched and packet switched networks (Internet). Voice over Internet Protocol (VoIP) is one of the most attractive and important service in telecommunication networks, current implementations of VoIP have two main types of architectures, which are based on H.323 and Session Initiation Protocol (SIP). However, when the voice traffic is transported over Internet, the packet based transmission may introduce impairments and it has influence on the Quality of Service (QoS) perceived by the end users. The voice quality of VoIP systems depends on many QoS parameters. Particularly, One Way Delay (OWD), jitter and Packet Loss Rate (PLR) have an important impact on voice quality. This survey presents the main concepts relating to the VoIP technology and quality of service issues

    Routing Protocols for Underwater Acoustic Sensor Networks: A Survey from an Application Perspective

    Get PDF
    Underwater acoustic communications are different from terrestrial radio communications; acoustic channel is asymmetric and has large and variable end‐to‐end propagation delays, distance‐dependent limited bandwidth, high bit error rates, and multi‐path fading. Besides, nodes’ mobility and limited battery power also cause problems for networking protocol design. Among them, routing in underwater acoustic networks is a challenging task, and many protocols have been proposed. In this chapter, we first classify the routing protocols according to application scenarios, which are classified according to the number of sinks that an underwater acoustic sensor network (UASN) may use, namely single‐sink, multi‐sink, and no‐sink. We review some typical routing strategies proposed for these application scenarios, such as cross‐layer and reinforcement learning as well as opportunistic routing. Finally, some remaining key issues are highlighted

    The issue of data exchange in the UHF band RFID system with an semi-passive transponder

    Get PDF
    The article discusses the specifics of data exchange in the UHF band RFID systems using semi-passive transponders. In addition to the antenna and the RFID chip, there is also an additional source of energy (eg. battery) in the structure of such transponder. The battery may be used to implement additional functions such as the ability to measure physical quantities (eg. temperature, humidity). In this regard, particular attention was paid to the discussion of phases of communication between transponder and RWD associated with additional data (measurement results). An analysis of transmitted data frames has been presented. The preliminary results of the measurements have shown that the number of memory block transmitted from transponder has an impact on the effectiveness of RFID system

    Effectiveness of C6T and W5H in Lean documentation

    Get PDF
    In the Evaluation of software development, Lean is oldest organizational methodology. To improve the performance Lean is having various versions. Documentation plays key role in estimating the performance of project. It is also having features like reorganization of development system. This paper focuses on drawbacks of documentation regarding lean methodology. Documentation will give clear vision and goals of product. To enhance the features of documentation C6T and W5H principles are applied

    Energy efficiency of small cell backhaul networks based on Gauss-Markov mobile models

    Full text link
    © The Institution of Engineering and Technology 2015. To satisfy the recent growth of mobile data usage, small cells are recommended to deploy into conventional cellular networks. However, the massive backhaul traffic is a troublesome problem for small cell networks, especial in wireless backhaul transmission links. In this study, backhaul traffic models are first presented considering the Gauss-Markov mobile models of mobile stations in small cell networks. Furthermore, an energy efficiency model of small cell backhaul networks with Gauss-Markov mobile models has been proposed. Numerical results indicate that the energy efficiency of small cell backhaul networks can be optimised by trade-off the number and radius of small cells in cellular networks

    Towards the use of unmanned aerial systems for providing sustainable services in smart cities

    Get PDF
    La sostenibilidad está en el centro de muchos campos de aplicación en los que el uso de los sistemas aéreos no tripulados (SUA) es cada vez más importante (por ejemplo, la agricultura, la detección y predicción de incendios, la vigilancia ambiental, la cartografía, etc.). Sin embargo, su uso y evolución están muy condicionados por el campo de aplicación específico para el que están diseñados y, por lo tanto, no pueden ser fácilmente reutilizados entre los diferentes campos de aplicación. Desde este punto de vista, al no ser polivalentes, podemos decir que no son totalmente sostenibles. Teniendo esto en cuenta, el objetivo de este trabajo es doble: por un lado, identificar el conjunto de características que debe proporcionar un UAS para ser considerado sostenible y demostrar que no hay ningún UAS que satisfaga todas estas características; por otra parte, presentar una arquitectura abierta y sostenible de los UAS que pueda utilizarse para construir UAS a petición para proporcionar las características necesarias en cada campo de aplicación. Dado que esta arquitectura se basa principalmente en la adaptabilidad del software y el hardware, contribuye a la sostenibilidad técnica de las ciudades.Sustainability is at the heart of many application fields where the use of Unmanned Aerial Systems (UAS) is becoming more and more important (e.g., agriculture, fire detection and prediction, environmental surveillance, mapping, etc.). However, their usage and evolution are highly conditioned by the specific application field they are designed for, and thus, they cannot be easily reused among different application fields. From this point of view, being that they are not multipurpose, we can say that they are not fully sustainable. Bearing this in mind, the objective of this paper is two-fold: on the one hand, to identify the whole set of features that must be provided by a UAS to be considered sustainable and to show that there is no UAS satisfying all these features; on the other hand, to present an open and sustainable UAS architecture that may be used to build UAS on demand to provide the features needed in each application field. Since this architecture is mainly based on software and hardware adaptability, it contributes to the technical sustainability of cities.• Ministerio de Economía y Competitividad y Fondos FEDER. Proyecto TIN2015-69957-R (I+D+i) • Junta de Extremadura y Fondo Europeo de Desarrollo Regional. Ayuda GR15098 y IB16055 • Parcialmente financiado por Interreg V-A España-Portugal (POCTEP) 2014-2020 program. Proyecto 0045-4IE-4-PpeerReviewe
    corecore