Search results for "Computer network"
showing 10 items of 1634 documents
A new Scheme for RPL to handle Mobility in Wireless Sensor Networks
2017
Mobile wireless sensor networks (WSNs) are characterised by dynamic changes in the network topology leading to route breaks and disconnections. The IPv6 routing protocol for low power and lossy networks (RPL), which has become a standard, uses the Trickle timer algorithm to handle changes in the network topology. However, neither RPL nor Trickle timer are well adapted to mobility. This paper investigates the problem of supporting mobility when using RPL. It enhances RPL to fit with sensors' mobility by studying two cases. Firstly, it proposes to modify RPL in order to fit with a dynamic and hybrid topology in the context of medical applications. Secondly, it investigates a more general case…
I-RP: Interference Aware Routing Protocol for WBAN
2018
The Wireless Body Sensor Networks (WBSN) have witnessed tremendous research interest because of their wide range of applications (medical and non-medical) in order to improve the quality of life. The healthcare applications of WBSN demands dissemination of patient’s data, reliably and in a timely manner. For this purpose, medical teams may use real-time applications for disseminating critical data such as blood pressure, ECG, and EEG. The critical data packets are highly delay sensitive that must reach intended destination within time constraints. Due to the exchange of real-time and multi-media data, some nodes or links may experience the significant level of interference in the network. C…
Power-constrained sensor selection and routing for cooperative detection in cognitive radios
2012
Given a spectrum-sensing network, a set of active nodes jointly aggregate sensed data at a preset frequency-band and simultaneously route this information to an arbitrarily chosen querying node through a power-constrained multi-hop path. Locally, each sensor node is assumed to be an energy-based detector. This work focuses on deriving algorithms that jointly optimize sensor selection and cooperative detection from which a power-efficient route to the querying node can be established, and then, a tree routing structure spanning the chosen nodes is constructed under a power budget constraint. Sensor information is sequentially aggregated along this optimized routing structure up to the queryi…
MAC strategies for single rendezvous multi-hop cognitive radio networks
2009
This paper presents two MAC strategies for multi-hop cognitive radio networks in single radio multi-channel cases. Both strategies use one of the idle multiple channels for communication among secondary users, and the network will leave the current channel and jump to another channel as a group if any primary user appears. The first strategy is based on a pre-defined pattern that will always tune to the next available channel when primary user emerges. The second one is based on the concept of connected dominating set in which a backbone is formed in the network in order to keep the continuity of the communication. The strategies are evaluated in both homogeneous and heterogeneous channels …
Adaptive live video streaming on low-cost wireless multihop networks for road traffic surveillance in smart cities
2021
Abstract Traffic surveillance is an important issue for Intelligent Transportation Systems (ITS) that helps detect incidents automatically, such as wrong-way drivers, still-standing vehicles and jams. Sometimes these systems require a fast and short-term deployment of video cameras. In these cases, ad-hoc networks could be a low-cost and feasible option, but they have poor performance for video delivery. Thus, we propose a smart live video adaptive streaming technique in order to transport video streams from the cameras to the external road traffic monitoring servers. To achieve this goal, these networks need a thorough study in order to analyze video quality under their inherent constraint…
Assignment of Roles and Channels for a Multichannel MAC in Wireless Mesh Networks
2009
International audience; A multichannel MAC improves throughput in wireless mesh networks by multiplexing transmissions over orthogonal channels. In this paper, we propose an efficient way for constructing the wireless mesh structure associated with Molecular MAC, a multichannel MAC layer designed for efficient packet forwarding. Molecular MAC outperforms other classical approaches, but requires a specific structure for efficient operation. First, we propose a centralized protocol that provides an upper bound for constructing such a molecular structure through a MILP (Mixed Integer Linear Programming) formulation that maximizes network capacity. Then, we present two distributed self-stabiliz…
An intrusion detection system for selective forwarding attack in IPv6-based mobile WSNs
2017
Selective forwarding attack is considered among the most dangerous attack in wireless sensor networks, particularly in mobile environment. The attackers compromise legitimate nodes and selectively drop some packets. In addition to that, the movement of some nodes increases link failures, collisions and packet loss. So, it will be more difficult to detect malicious nodes from legitimates ones. This paper focuses on detecting selective forwarding attackers in IPv6-based mobile wireless sensor networks when the standardized IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) is used. Contrarily to previous works which propose solutions to detect selective forwarding attack in static w…
A Novel Architecture for Inter-FPGA Traffic Collision Management
2014
International audience; —with the increasing complexity of various communi-cations and applications, Network-On-Chip (NoC) is one of the most efficient communication structures. Multi-FPGA platforms are considered as the most appropriate experimental solutions to emulate a large size of MPSoCs (Multi-Processor System-on-Chip) based on a NoC. The deployment of the NoC into several FPGAs requires the use of inter-FPGA communication links. The number and performance of external links restrict the bandwidth of communication. Currently, the number of inter-FPGA signals is considered as a substantial problem in NoC implemented on Multi-FPGA architectures. In this paper, we propose the integration…
Performance of H.264 compressed video streams over 802.11b based MANETs
2004
We address the problem of video streams transmission in 802.11b based mobile ad-hoc networks (MANETs). Through the study of the delivery of a live encoded video stream, we expose the characteristics of different routing protocols and the infeasibility to provide QoS. The analysis shows the impact of a MANET on H.264 real-time video flows in terms of packet loss, end-to-end delay, jitter and distortion, and the behavior of H.264 error resilience tools in order to determine their effectiveness on such network scenarios. The results show that video traffic has demands that are hard to be met by a standard MANET, and that improvements are required in terms of routing protocols and QoS provision…
Securing AODV routing protocol against black hole attack in MANET using outlier detection scheme
2017
Imposing security in MANET is very challenging and hot topic of research science last two decades because of its wide applicability in applications like defense. Number of efforts has been made in this direction. But available security algorithms, methods, models and framework may not completely solve this problem. Motivated from various existing security methods and outlier detection, in this paper novel simple but efficient outlier detection scheme based security algorithm is proposed to protect the Ad hoc on demand distance vector (AODV) reactive routing protocol from Black hole attack in mobile ad hoc environment. Simulation results obtained from network simulator tool evident the simpl…