Search results for "Computer network"
showing 10 items of 1634 documents
A hybrid bio-inspired approach to solving the routing problem in mobile ad hoc networks
2018
A mobile ad hoc network (MANET) is an autonomous system of mobile hosts (nodes) connected by a wireless link. However, the problem of designing routing protocols poses challenges to researchers due to the unpredictable and dynamic nature of ad hoc networks. Hence, bio-inspired algorithms are widely used to design adaptive routing strategies for MANETs. This paper proposes a routing protocol based on the hybridisation of ant colony optimisation (ACO) and 2-opt heuristic with the optimisation of ACO parameters. Given the vast scope of the parameters, a genetic algorithm is used to minimise the complexity of the problem. The implementation of the method is realised by MATLAB. To valid the resu…
SDN controllers security issues
2017
Software-Defined Networking (SDN) is essentially varying the way we design and manage networks, which makes a communication network programmable. In SDN, a logically centralized controller has straight control over the packet-handling functions of the network switches, using a standard, open API (Application Programming Interface) such as OpenFlow. OpenFlow is a broadly used protocol for software-defined networks (SDNs) that presents a new model in which the control plane is inattentive from the forwarding plane for the network devices. In SDN approach centralized entities called "controllers" perform like network operating systems run dissimilar applications that accomplish and control the…
Reliable Coverage with Circumferential WMSNs
2021
This work tackles the closed peripheral coverage issue. Such circumferential surveillance is essential in numerous realistic applications where the goal is to ensure rapid detection of any unauthorized entry/exit of the monitored area. To respond to these requirements, peripheral WMSNs can be rapidly deployed around areas of interest (e.g., temporary military camps, natural or nuclear disasters, etc.). While it seems simple, this solution raises two major challenging issues. First, checking whether the deployed peripheral WMSN forms a closed shape around the monitored region. That is, any object trying to leave or access this area must be instantaneously detected by at least one multimedia …
Evaluating Bluetooth Performance as the Support for Context-Aware Applications
2005
We present an experiment relative to the use of the Bluetooth wireless technology to provide network support for context-aware applications. We describe an approach to provide network interconnection using a combination of wireless and wired network technologies. We also describe the steps taken to create a Bluetooth based context-aware application. We, finally, evaluate, using a small test-bed and simulation the overall performance of this technology when adopted in the area of context-aware and ubiquitous computing.
MAC learning
2016
Cognition as a way to deal with the challenges of future wireless networks has been largely considered by the recent literature, with a main focus on physical layer adaptability and dynamic spectrum access. In this demo, we show how a simple cognition mechanism can be also applied at the MAC layer, by exploiting the emerging paradigm of programmable wireless cards. The idea is using the formal definition of simple MAC protocol components and platform-independent representation of channel events gathered from the wireless node, for emulating the behavior of protocols which are not currently running on the network, learning about their expected performance, and dynamically reconfiguring the w…
Serial In-network Processing for Large Stationary Wireless Sensor Networks
2017
International audience; In wireless sensor networks, a serial processing algorithm browses nodes one by one and can perform different tasks such as: creating a schedule among nodes, querying or gathering data from nodes, supplying nodes with data, etc. Apart from the fact thatserial algorithms totally avoid collisions, numerous recent works have confirmed that these algorithms reduce communications andconsiderably save energy and time in large-dense networks. Yet, due to the path construction complexity, the proposed algorithmsare not optimal and their performances can be further enhanced. To do so, in the present paper, we propose a new serial processing algorithm that, in most of the case…
Adaptive SDN-based architecture using QoE metrics in live video streaming on Cloud Mobile Media
2017
The increasing adoption of smart phones, the increased access to mobile broadband networks and the availability of public cloud infrastructures are aligning to the next generation of truly ubiquitous multimedia services, known as Cloud Mobile Media (CMM) services. Nevertheless, due to an inherit higher and variable end to end delay mainly as a result of the virtualization process, new challenges appear in particular for live video streaming applications in order to keep a good Quality of Experience of the delivered video. Thus, to keep client's satisfaction at good levels in terms of Mean Opinion Score (MOS), we propose an adaptive Software Defined Networking (SDN)-based architecture runnin…
IMPACT OF TIMETABLE SYNCHRONIZATION ON HUB CONNECTIVITY OF EUROPEAN CARRIERS
2016
This paper evaluates the net impact of timetable synchronization on the connectivity of the key European carriers at their main hubs. We measure hub connectivity using a weighted connectivity score (WCS) that takes into account the number and the trip time related quality of flight connections. Based on WCS, we compare hub performance resulting from the existing schedule against a random expectati on calculated from multiple randomized schedule simulations. In each simulated schedule scenario we randomly vary the flight departure and arrival times within the operation hours at a hub and at outbound stations keeping all other flight parameters from the real schedule unchanged.We observe that…
Energy Efficient Resource Allocation for Wireless Power Transfer Enabled Collaborative Mobile Clouds
2016
In order to fully enjoy high rate broadband multimedia services, prolonging the battery lifetime of user equipment is critical for mobile users, especially for smartphone users. In this paper, the problem of distributing cellular data via a wireless power transfer enabled collaborative mobile cloud (WeCMC) in an energy efficient manner is investigated. WeCMC is formed by a group of users who have both functionalities of information decoding and energy harvesting, and are interested for cooperating in downloading content from the operators. Through device-to-device communications, the users inside WeCMC are able to cooperate during the downloading procedure and offload data from the base sta…
Dissemination protocol for Heterogeneous Cooperative Vehicular Networks
2012
International audience; The difficulties associated with network connectivity, unreliable channels, and city environment characteristics make data dissemination task in vehicular urban networks a real challenge. Recently, some interesting solutions have been proposed to perform data dissemination in this environment. Starting from the analysis of these solutions, we present a new dissemination protocol named DHVN (Dissemination protocol for Heterogeneous Cooperative Vehicular Networks) that considers: (i) roads topology, (ii) network connectivity and possible partitioning in case of low traffic density, and (iii) heterogeneous communication capabilities of the vehicles. We compare our proto…