Search results for "working"
showing 10 items of 2747 documents
Algorithmic Complexity Vulnerability Analysis of a Stateful Firewall
2016
Algorithmic complexity vulnerabilities are an opportunity for an ad-versary to conduct a sophisticated kind of attack i.e. on network infrastructure services. Such attacks take advantage of worst case time or space complexity of algorithms implemented on devices in their software. In this paper we address potential risks introduced by such algorithmic behavior in computer networks in particular on a stateful firewall. First we introduce the idea and theoretical background for the attack. We then describe in full detail a successfully con-ducted attack which takes advantage of the worst case computational complexi-ty of O(n2) of a hash table data structure used to store active sessions. The …
Flexible Spare Core Placement in Torus Topology based NoCs and its validation on an FPGA
2021
In the nano-scale era, Network-on-Chip (NoC) interconnection paradigm has gained importance to abide by the communication challenges in Chip Multi-Processors (CMPs). With increased integration density on CMPs, NoC components namely cores, routers, and links are susceptible to failures. Therefore, to improve system reliability, there is a need for efficient fault-tolerant techniques that mitigate permanent faults in NoC based CMPs. There exists several fault-tolerant techniques that address the permanent faults in application cores while placing the spare cores onto NoC topologies. However, these techniques are limited to Mesh topology based NoCs. There are few approaches that have realized …
Computer networks stability independence of the queuing delays
2015
Communication in intelligent computer networks is an indispensible attribute of the dataflow quality in Web traffic. We propose a model that investigates intelligent computer networks stability while specifying its limits. Packet queuing delay affects the performance of the network, and especially its stability. If the network is presented as a dynamic system in block diagram form, we compute a transfer function and determine the quasi-polynomial system. The characteristic polynomial distribution of zeros of complex variable quasi-plane determines the boundaries of the network stability. The approach relies on estimation of the network system's transfer functions and its quasi-polynomial. C…
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…