Packet Delivery Latency Research Articles

Modified Light Weight distributed QoS Algorithm for wide area ad hoc networks

SummaryThe direction and velocity of a node are the most important parameters to create a valuable path in ad hoc networks. A valuable path is one that has a longer life time and more durability than others. As we know, the durability of a path is under the influence of the nodes' velocity. This paper proposes an algorithm to provide QoS in ad hoc networks. The proposed algorithm entitled Modified Light Weight distributed QoS Algorithm, considering the direction and relative velocity of the nodes and predicting the value of link durability, chooses a path with longer duration time, minimizes the link breaks, and improves QoSs. We implemented it in a simulation environment by using the Network Simulator Version 2 software and evaluated the effectiveness of it in packet delivery ratio, packet delivery latency, average end‐to‐end delay, routing overhead, and dropped packets. The simulation results demonstrate that Modified Light Weight distributed QoS Algorithm improves the QoS parameters in ad hoc networks.

Jamming-Resilient Multipath Routing Protocol for Flying Ad Hoc Networks

As a result of the rapid technological advances on electronic, sensors and communication technologies, and increasingly popular multi-sized unmanned aerial vehicles, also referred to as drones, flying ad hoc networks (FANETs) are rapidly proliferating and leading the emergence of Internet of Drones and its applications. Because of the versatility, flexibility, easy installation, and relatively small operating expenses of drones, FANETs have enormous potential in the public and civil domains. However, due to unique characteristics of FANETs, routing demands of FANETs go beyond the needs of mobile ad hoc networks and vehicular ad hoc networks. In this paper, we propose a jamming-resilient multipath routing protocol, also called JarmRout , so that intentional jamming and disruption or isolated and localized failures do not interrupt the overall network performance of FANETs. To achieve this goal, the JarmRout relies on a combination of three major schemes that are link quality scheme, traffic load scheme, and spatial distance scheme. We present a simple analytical model and its numerical result in terms of RREP packet reception rate of source node. We also evaluate the proposed routing protocol through extensive simulation experiments using the OMNeT++ and compare its performance with three representative routing protocols that are dynamic source routing, optimized link state routing, and split multipath routing. Simulation results show that the JarmRout can not only improve packet delivery ratio and packet delivery latency but also can reduce end-to-end communication outage rate without introducing extra communication overhead, indicating a viable approach to improve network resiliency in the presence of malicious jammers in FANETs.

Resource prediction-based routing using agents in mobile ad hoc networks

QoS outing in multimedia applications over MANET is affected by limited resources, shared channel, unpredictable mobility, improper load balancing, and variation in signal strength. Existing works on MANET QoS routing focuses on only one of the factor such as bandwidth, mobility or energy neglecting dependent behaviour. In this paper, resource prediction-based routing is proposed wherein intelligent agents identify routes for communication with adequate future availability of buffer-space, energy and bandwidth resources considering mobile nodes. It has four steps of execution: resource prediction, resource prediction factor computation, route establishment, and route maintenance. Resources are predicted to compute resource prediction factors for reliable route establishment and route maintenance against link and node failure. Simulation results show an improvement in terms of packet delivery ratio, packet delivery latency, memory overhead and energy consumption.

Classification approach to avoid link failures in wireless sensor networks in mobile virtual communities and teleworking

Security issues are the primary issues in wireless sensor networks (WSN) due to its large network coverage and number of nodes. The attackers in WSN attack the particular node which has a low energy level and converts this node into malicious node. The formation of malicious node is the primary reason for link failures between nodes. This paper proposes an efficient methodology to detect the malicious nodes in WSN using feed forward back propagation neural network classifier. This classifier differentiates the malicious node from trusty node based on the extracted features of the test node. The performance of the proposed malicious node detection system is analysed in terms of detection rate, packet delivery ratio (PDR) and latency. The experimental results are compared with state-of-art methods.

Topology-Aware Optimal Subgrouping and Subscheduling for Generalized Explicit Multicasting on Internet

eXplicit multicasting (Xcast) is a protocol to send data to multiple receivers in an efficient way. Compared with traditional stateful multicast, Xcast is based on a stateless approach that scales better in number of groups. Unfortunately, the original Xcast brings up new challenges such as the scalability of group size and efficiency issue. Therefore, Multiple Xcast (MXcast) and Generalized Xcast (GXcast) were proposed to retard the limitation of the group size by reconstructing the multicast group into multiple subgroups and transferring multiple Xcast packets to different subgroups, respectively. In this paper, we propose various subgrouping schemes and evaluate their performance based on hybrid simulation experiments. The results show that it can save up to 36.7% bandwidth consumption from Xcast to our proposed Optimal GXcast in Voice over Internet Protocol (VoIP). The results reflect that the proposed scheme can improve the scalability of group size, achieve minimal packet delivery latency, reduce both network bandwidth consumption and source loading compared with the unicast and original Xcast, MXcast, and GXcast.

A prediction-based asynchronous MAC protocol for heavy traffic load in wireless sensor networks

Radio transceiver often consumes most of energy in a sensor node. To achieve low power consumption, every node periodically schedules its radio transceiver into sleep or active state, which is usually called duty cycle mechanism in MAC protocol. In this paper, we design a novel Prediction-Based Asynchronous MAC protocol (PBA-MAC) for heavy traffic load in wireless sensor networks. PBA-MAC applies an efficient wakeup mechanism to save the energy of a sensor node as much as possible. It reduces communication cost by enabling a sender to predict the intended receiver’s wakeup time, without introducing unnecessary idle listening or overhearing cost. In addition, it introduces an exponential advance mechanism to handle the prediction error caused by clock drift and hardware platform latency. More importantly, its backcast-based retransmission characteristic can efficiently resolve severe wireless collisions caused by concurrent traffic flows. The PBA-MAC is implemented in Contiki operating system. We compare PBA-MAC to some existing energy-efficient MAC protocols. The experimental results show that PBA-MAC significantly improves network energy efficiency and reduces packet delivery latency even under heavy traffic load.

Novel routing protocol scheme for real-time applications in mobile Ad Hoc networks

In mobile Ad Hoc networks (MANETs), flooding-based route discovery is usually preferred in order to set up the route with reliability between transmission pair. However, this approach may cause a serious contention in transmission between adjacent nodes and a considerable amount of control packets. In addition, most of Ad Hoc routing protocols establish the route with minimum hop count. Consequently, the performance of Ad Hoc routing protocol is considerably affected by link (or route) duration since the network comprises the nodes with unrestricted mobility and constrained range in transmission. This paper proposes novel routing protocol that aims to (1) minimize routing overhead in route discovery procedure, and (2) guarantee a reliable and fast packet delivery between source and destination, especially in providing real-time applications over MANETs. To achieve this objective, we introduce relay region (RR) within the transmission range of nodes in order to select optimal next relaying nodes for supporting specific application requirements in route discovery procedure. The RR is defined by the limited distance progress in transmission to next relaying node in order to maintain the established route for an arbitrary length of time (i.e., route duration) while meeting packet delivery reliability and delay constraints. In performance evaluation, the simulation results showed that the proposed scheme can significantly improve the performance in comparison with the previous routing algorithms in terms of packet delivery ratio and packet delivery latency, reducing transmission redundancy in route discovery procedure.

ADC: an Adaptive Data Collection Protocol with Free Addressing and Dynamic Duty-Cycling for Sensor Networks

To improve network lifetime of the battery-powered sensors for data collection, duty-cycling is commonly adopted at the link layer. A fixed duty cycle may cause a long packet delivery latency, low network capacity, and poor energy efficiency, especially in a frequently-reporting application. Moreover, considering a heterogeneous network constituted of various sensor platforms from different manufacturers, not only is node addressing with regard to address definition, management, and allocation difficult and costly, but also different addressing schemes will obstruct cross-platform communications. Based on the above considerations, this paper proposes an Adaptive Data Collection (ADC) with two features naturally and seamlessly integrated, i.e., free addressing and dynamic duty-cycling, to improve load adaptivity and energy efficiency, and to better accommodate network heterogeneity. ADC has been implemented in the Contiki Operating System. The evaluations based on a heterogeneous testbed consisting of two hardware platforms and a set of simulations in Cooja simulator consisting of three fully emulated platforms have demonstrated its practicality and efficacy.

A Multi-Synchronous Bi-Directional NoC (MBiNoC) architecture with dynamic self-reconfigurable channel for the GALS infrastructure

To enhance the performance of on-chip communications of Globally Asynchronous Locally Synchronous Systems (GALS), a dynamic reconfigurable multi-synchronous router architecture is proposed to increase network on chip (NoC) efficiency by changing the path of the communication link in the runtime traffic situation. In order to address GALS issues and bandwidth requirements, the proposed multi-synchronous bidirectional NoC’s router is developed and it guarantees higher packet consumption rate, better bandwidth utilization with lower packet delivery latency. All the input/output ports of the proposed router behave as a bi-directional ports and communicate through a novel multi-synchronous first-in first-out (FIFO) buffer. The bidirectional port is controlled by a dynamic channel control module which provides a dynamic reconfigurable channel to the router itself and associated sub-modules. This proposed multi-synchronous bidirectional router architecture is synthesized using Xilinx ISE 14.7 and FPGA Virtex 6 family device XC6VLX760 is considered as target technology and its performance is evaluated in terms of power, area and delay.

An Efficient Interactive Model for On-Demand Sensing-As-A-Servicesof Sensor-Cloud.

This paper proposes an efficient interactive model for the sensor-cloud to enable the sensor-cloud to efficiently provide on-demand sensing services for multiple applications with different requirements at the same time. The interactive model is designed for both the cloud and sensor nodes to optimize the resource consumption of physical sensors, as well as the bandwidth consumption of sensing traffic. In the model, the sensor-cloud plays a key role in aggregating application requests to minimize the workloads required for constrained physical nodes while guaranteeing that the requirements of all applications are satisfied. Physical sensor nodes perform their sensing under the guidance of the sensor-cloud. Based on the interactions with the sensor-cloud, physical sensor nodes adapt their scheduling accordingly to minimize their energy consumption. Comprehensive experimental results show that our proposed system achieves a significant improvement in terms of the energy consumption of physical sensors, the bandwidth consumption from the sink node to the sensor-cloud, the packet delivery latency, reliability and scalability, compared to current approaches. Based on the obtained results, we discuss the economical benefits and how the proposed system enables a win-win model in the sensor-cloud.

L-MAC: A wake-up time self-learning MAC protocol for wireless sensor networks

This paper analyzes the trade-off issue between energy efficiency and packet delivery latency among existing duty-cycling MAC protocols in wireless sensor networks for low data-rate periodic-reporting applications. We then propose a novel and practical wake-up time self-learning MAC (L-MAC) protocol in which the key idea is to reuse beacon messages of receiver-initiated MAC protocols to enable nodes to coordinate their wakeup time with their parent nodes without incurring extra communication overhead. Based on the self-learning mechanism we propose, L-MAC builds an on-demand staggered scheduler to allow any node to forward packets continuously to the sink node. We present an analytical model, and conduct extensive simulations and experiments on Telosb sensors to show that L-MAC achieves significant higher energy efficiency compared to state-of-the-art asynchronous MAC protocols and a similar result of latency compared to synchronous MAC protocols. In particular, under QoS requirements with an upper bound value for one-hop packet delivery latency within 1 s and a lower bound value for packet delivery ratio within 95%, results show that the duty cycle of L-MAC is improved by more than 3.8 times and the end-to-end packet delivery latency of L-MAC is reduced by more than 7 times compared to those of AS-MAC and other state-of-the-art MAC protocols, respectively, in case of the packet generation interval of 1 min. L-MAC hence achieves high performance in both energy efficiency and packet delivery latency.

Modeling and Analyzing Duty-Cycling Pipelined-Scheduling MAC for Linear Sensor Networks

Linear sensor networks (LSNs) have recently attracted increasing attention due to the vast requirements on the monitoring and surveillance of a structure or an area with a linear topology. However, there is not a lot of work on network modeling and analysis based on a duty-cycling medium access control (MAC) protocol for LSNs. In this paper, we model a duty-cycling MAC with a pipelined-scheduling feature for an LSN, where each node is responsible for monitoring a certain area and can generate packets according to its sensed results. Based on the model, we analyze the network performance in terms of system throughput, active time ratio per cycle of each node, and packet delivery latency. Through extensive OPNET-based simulations, we validate the model and reveal the dependence of the network performance on various system parameters. Apart from enabling the effective estimation of the protocol performance by using our model, we believe that our model and analysis could provide an insightful understanding on the behavior of a duty-cycling MAC protocol and aid in its design and optimization for a multihop LSN.

Actor-oriented directional anycast routing in wireless sensor and actor networks with smart antennas

Current routing protocols in wireless sensor and actor networks (WSANs) shows a lack of unification for different traffic patterns because the communication for sensor to actor and that for actor to actor are designed separately. Such a design poses a challenge for interoperability between sensors and actors. With the presence of rich-resource actor nodes, we argue that to improve network lifetime, the problem transforms from reducing overall network energy consumption to reducing energy consumption of constrained sensor nodes. To reduce energy consumption of sensor nodes, especially in challenging environments with coverage holes/obstacles, we propose that actor nodes should share forwarding tasks with sensor nodes. To enable such a feature, efficient interoperability between sensors and actors is required, and thus a unified routing protocol for both sensors and actors is needed. This paper explores capabilities of directional transmission with smart antennas and rich-resource actors to design a novel unified actor-oriented directional anycast routing protocol (ADA) which supports arbitrary traffic in WSANs. The proposed routing protocol exploits actors as main routing anchors as much as possible because they have better energy and computing power compared to constraint sensor nodes. In addition, a directional anycast routing approach is also proposed to further reduce total delay and energy consumption of overall network. Through extensive experiments, we show that ADA outperforms state-of-the-art protocols in terms of packet delivery latency, network lifetime, and packet reliability. In addition, by offer fault tolerant features, ADA also performs well in challenging environments where coverage holes and obstacles are of concerns.

An Efficient Approach for Malicious Node Detection in Wireless Sensor Networks Using Classifier

Recently, wireless sensor networks (WSNs) have received much attention as a means for collecting and utilizing data from real world. The number of WSN applications has been increasing widely and the application range is expected to spread. WSN is a network composed of a large number of sensor nodes with limited radio capabilities and one or few sinks that collect data from sensor nodes. Residual nodes are the malicious nodes in WSN which degrades the performance of the WSN. The malicious node detection is a multifaceted crisis in WSN due to its analogous distinctiveness with other nodes in with other nodes in WSN. Trust model is developed to extract the features of the nodes in the sensing area. Further, feed forward back propagation algorithm is applied on the extracted features to detect the malicious nodes in WSN. The detected malicious node is held in a blackhole list and all other nodes participating in the routing of the message are warned to stop communicating with the malicious node in that list. The malicious node detection system is analyzed in terms of sensitivity, specificity, accuracy, packet delivery ratio, latency, and detection rate with state of art methods.

Asynchronous Hybrid Duty Cycle MAC Protocol for Wireless Sensor Networks

Energy conversation is one of the primary objectives of duty cycle MAC protocols. Different synchronous and asynchronous duty cycle MAC protocols have been proposed in recent years. These protocols perform well under low traffic loads, but efficiency of these protocols degrade under high traffic loads. We present an asynchronous hybrid duty cycle MAC protocol called Hybrid MAC (H-MAC), which uses both sender and receiver initiated mechanisms to combat the packet delivery latency. In H-MAC each node schedules its sleep and wake up time based on cross layer routing information on the receiver initiated part and on the sender initiated part each sender chooses its wake up time based on the receiver's wake up information. We have evaluated HMAC in diverse network under dynamic traffic loads. Experiments reveal that, H-MAC significantly reduces packet delivery latency and energy consumption compared to RIMAC.

Design and performance evaluation of distributed mobility management schemes for network mobility

Distributed Mobility Management (DMM) is a current alternative paradigm for developing IP mobility management schemes to address the centralised mobility management problems in existing IP mobility management schemes. This is to allow these schemes to cope with the current increase in the number of mobile users and mobile data traffic volume, as well as the trend in the mobile Internet towards a flat architecture. To date, schemes׳ development based on DMM approach is still at preliminary stages in the IETF, and there is no current standard in place. In this paper, we develop network-based DMM schemes for the Network Mobility (NEMO). The schemes are developed for non-nested and nested NEMO scenarios – with the goal of mitigating the sub-optimal routing, high packet overhead and packet delivery latency, especially in a nested NEMO scenario, due to the employment of a centralized mobility management approach in NEMO. Additionally, the proposed scheme improves the packet delivery and location update (i.e., binding update) costs. The paper presents in detail the schemes’ design, operation mechanism, and the performance evaluation (through analytical and simulation in ns-2). Both the analytical and simulation results show that the proposed schemes yield a significant improvement – in terms of reducing packet overhead and packet delivery latency, as well as binding update and packet delivery costs.

RM-MAC: a reservation based multi-channel MAC protocol for wireless sensor networks

Convergecast is a general communication pattern of wireless sensor networks (WSNs) in which sensed data is collected from outlying sensor nodes and is transmitted to a sink node. In this paper, we consider periodic convergecast, in which data packets are generated and transmitted repeatedly with a certain interval. To support the periodical packet delivery efficiently, we propose a reservation based multi-channel MAC protocol (RM-MAC) which employs a time reservation mechanism. Periodical packet delivery allows receiver nodes to recognize when the next packet is transmitted, which makes the nodes reserve the time for the next packet transmission. Consequently, our proposed mechanism can guarantee minimum delivery latency from source nodes to a sink node. Furthermore, RM-MAC provides a collision resolution mechanism which coordinates the reserved periodical transmissions among multiple sender nodes. It can prevent repeated collisions caused by the multiple-senders-single-receiver problem. We implement RM-MAC by using an ns-2 simulator to compare its performance with other protocols. The simulation results show that RM-MAC outperforms existing protocols in terms of energy efficiency and packet delivery latency.

DS-MAC: An energy efficient demand sleep MAC protocol with low latency for wireless sensor networks

Duty cycling mechanism has been widely used to conserve energy that consumed by idle listening in wireless sensor networks, while fixed duty cycling introduces transmission latency in packet delivery. End to end latency is one of the most significant factors of packets loss in wireless sensor nodes, and many techniques have been proposed based on listening adaptively to reduce delay, which are mainly designed for light traffic loads. In this paper, we propose a novel asynchronous duty cycling MAC protocol, called demand sleep MAC (DS-MAC) that allows nodes to adjust their sleep time adaptively according to the amount of the received data packets in order to efficient and effective communication in the dynamic traffic load. DS-MAC protocol attempts to transmit a series of short token packets to wake up the receiver, which avoids the overhearing problem. Nodes in DS-MAC put the prediction field into ACK packets, which decreases the waiting delay of source node. Comprehensive simulation shows that when there are variable flows, such as broadcast traffic or transmissions from hidden nodes, DS-MAC significantly decreases waiting delay and energy consumption.

A Survey on Obstacle Modeling Patterns in Radio Propagation Models for Vehicular Ad Hoc Networks

Vehicular ad hoc networks (VANETs) form an evolving field of wireless technology that focuses on a wide range of useful applications from safety-related applications to infotainment services. Radio propagation models (RPMs) in VANETs require a high level of realistic detail due to mobility, the nature of the network, technology limitations and urgency of information dissemination. Hence, developing realistic RPMs in VANETs is a challenging task. Nonetheless, a number of traditional models are considered realistic; however, the absence of a required level of detail is a critical aspect of currently employed RPMs. For instance, modeling obstacles in VANETs is a challenging research perspective. Two types of radio obstacles exist in an urban transportation environment: moving obstacles and static obstacles, both of which block radio signals in vehicle-to-infrastructure and vehicle-to-vehicle communication. In this paper, a thematic taxonomy of existing RPMs is proposed and the major challenges involved in modeling realistic radio propagation for VANETs, especially in urban environments, are presented. Existing RPMs are classified and compared using the proposed taxonomy. These RPMs are grouped according to obstacle modeling pattern and are analyzed using important parameters, such as received signal strength, packet delivery ratio, delivery latency and average path length. Issues and challenges with existing RPMs are put forward and recommendations that may be helpful for developing realistic RPMs are made.

Mobility management with distributed mobility routing functions

Currently, IP mobility management solutions standardized by IETF rely on a centralized and static mobility approach, whereby a central mobility anchor manages mobility signaling and data traffic forwarding. All data traffic sent to a mobile node (MN) traverse the central mobility anchor regardless the current point of attachment of the MN in the Internet. Consequently, the packets follow a non-optimal path via the central mobility anchor which is typically located in the MN's home network, and result to increase in packet delivery latency. This paper discusses a distributed mobility management mechanism that releases the burden of the central mobility anchor by splitting the mobility management functions of the mobility anchor and co-locating the mobility routing function at the gateway of each sub-network. This mechanism optimizes the data path of the MN that has moved to visited networks, which reduces the packet delivery latency. Moreover, the mechanism is extended to achieve seamless handover when the MN moves between visited networks. Through simulation under NS-2, the performance of the packet delivery latency, handover delay and packet loss is studied and analyzed with respect to varying network load and increasing distance of the MN's home network from the visited networks. Simulation results show the improvement in packet delivery latency as compared to using non-optimized paths. Moreover, the results also verify the achievement of seamless handover when an MN moves between visited networks.