Number Of Transmitted Packets Research Articles

Compressive Sensing for Remote Flood Monitoring

Although wireless sensor networks are considered as one of the prominent solutions for flood monitoring, the energy constraint nature of the sensors is still a technical challenge. In this letter, we tackle this problem by proposing a novel energy-efficient remote flood monitoring system, enabled by compressive sensing. The proposed approach compressively captures water level data using i) a random block-based sampler, and ii) a gradient-based compressive sensing approach, at a very low rate, exploiting water level data variability over time. Through extensive experiments on real water-level dataset, we show that the number of packet transmissions as well as the size of packets are significantly reduced. The results also demonstrate significant energy reduction in sensing and transmission. Moreover, data reconstruction from compressed samples are of high quality with negligible degradation, compared to classic compression techniques, even at high compression rates.

Energy conservation in query driven wireless sensor networks

Network topology used to connect sensor nodes is important factor in wireless sensor networks (WSNs) that affect the energy usage of any network. Proper topology connection thereby reduces energy usage of network by reducing number of packet transmissions. Therefore node connection must be optimized in wireless sensor networks. Hence we introduce a new multiple tree based architecture of sensor network, comprising of heterogeneous nodes, to develop an energy efficient query processing WSN application. This article proposes Multi-tree and Multiple-tree algorithms for improving network parameters in the usual data collection WSN application scenarios. A multi-tree simply suggests a strategy where similar parameter type sensors are arranged in a tree based topology so as to reduce the energy consumption as well as the end to end delay in data communication. The Multiple-tree exemplifies a more effective way of query result propagation in data centric applications where delay requirements are not very stringent.

Energy Efficient Communication Framework for Target Coverage using Trust Concepts

Target coverage is a challenging task in the field of wireless sensor networks aiming to observe a set of critical targets while considering the limited resources and the network lifetime is improved. The paper proposes an approach to : i) determine the strategy according to which the critical targets can be monitored while satisfying a certain confidence level. ii) determine the maximum and minimum number of nodes which can guarantee the coverage, iii) determine the optimal number of active nodes for various deployment strategies, iv) to determine a routing mechanism using either single hop/multi hop communication based on the reachability of the node to the base station and iv) to develop an aggregation protocol which can reduce the redundancy and number of packet transmissions. The proposed protocol is based on the two level aggregation at the set cover level and at the cluster level using the concept of Locality Sensitive Hashing (LSH) and Jaccard Similarity measure. The efficiency of the proposed aggregation mechanism is determined for various data sets of multiple dimensions. The results obtained through the simulations show the improvement in the network performance with respect to the network longevity, coverage, reliability and of the data transmission as compared to the Boolean coverage model

Modeling a Novel Network Coding Aware Routing Protocol for Enhancement of Network Performance in Wireless Mesh Network

A Wireless Mesh Network (WMN) is a multi-hop network that gains the benefits of low deployment cost, fast access speed, expanded service coverage and large network capacity. However, the multi-hop communication in WMNs limits the throughput capacity due to increased number of packet transmissions. As a result, network coding is a recently emerged paradigm that can enhance the throughput capacity (i.e. network throughput) by minimizing the quantity of network workload and at the same time it ensures the data transfer among all the users. Further, with network coding the transmission effectiveness of a node can be improved by encoding (combining) several packets collectively and verifies whether the coding strategies is satisfied or not. Subsequently, if the coding strategies are satisfied then it transmits only the resultant encoded packet to the desired destination. In other words, network coding can improve the network throughput in WMNs by minimizing the transmission counts needed to transfer several packets to the destination. It should be noted that, while employing network coding in WMNs there are several challenges that should be compensated such as (i) identifying packets that can be combined (encoded) collectively and (ii) integrating the coding strategies in routing protocols. In this paper, we proposed a new mesh routing protocol that integrates network-coding called as Network Coding Aware Routing (Net-CART) protocol. Therefore, to enjoy the whole benefit of network coding a Net-CART protocol uses the innovative routing metric called Code-Aware and Load-Aware Routing Metric. Additionally, to identify numerous ‘coding structures’ and to support number of ‘packet encodings’ an improved set of coding strategies known as Enhanced Universal Coding Strategies is also proposed. The proposed Net-CART protocol comprising an improved set of coding strategies and a new routing-metric considers both the coding-opportunities and “network workload”. The simulation study carried out in wide forms of network configurations showed that Net-CART gives more fairness performances than other protocols.

Reliable and Energy-Efficient Data Forwarding in Industrial Wireless Sensor Networks

Reliable and energy-efficient data forwarding is significant for industrial Internet of Things (IoT) applications. A routing protocol called Network Coding and Power Control based Routing (NCPCR) is presented for unreliable wireless networks to save energy. The proposed NCPCR incorporates network coding mechanism and considers dynamic transmit power and the number of packet transmissions. In addition to the optimal transmit power, we derive the probability of successful decoding an encoded packet to achieve the network coding gain. The proposed NCPCR adopts the derived network coding gain in making intelligent decisions on whether to apply network coding or not such that energy consumption is significantly reduced. Simulation results show that the proposed NCPCR outperforms existing routing protocols in terms of lower energy consumption.

FEC-Seluge: Efficient, reliable, and secure large data dissemination using erasure codes

Secure data dissemination is indispensable in various network systems such as wireless sensor networks (WSNs) and Information-Centric Networks. Several approaches have been proposed for secure data dissemination while adopting forward error correction techniques (e.g., erasure codes) for efficiency. In particular, an approach named LR-Seluge was proposed to achieve efficient, secure data dissemination by integrating erasure codes into Seluge, a previous solution for secure data dissemination in WSNs. However, despite its efficiency in reducing the number of packet transmissions, LR-Seluge still introduces long dissemination delays.In this paper, we develop a new approach called FEC-Seluge, which is aimed at reducing both the dissemination delay and the number of packet transmissions by taking full advantage of erasure codes. Our key contribution is a technique to securely estimate the optimal amount of redundancy of erasure coding to balance loss-tolerance capabilities and bandwidth consumption. In addition, we develop a novel proactive transmission mechanism, which considerably improves the efficiency by effectively tolerating packet losses. We evaluated FEC-Seluge through experiments in a testbed environment. The experimental results show that FEC-Seluge outperforms LR-Seluge by about 30% and 23% in terms of the dissemination delay and the number of packet transmissions, respectively.

A Joint Network Coding and Device Association Design for Optimal Local Data Exchange in Fiber-Wireless Access Network

For many emerging mobile broadband services and applications, the source and destination are located in the same local region. Consequently, it is very important to design access networks to facilitate efficient local data exchange. In the past few years, most existing studies focus on either the wired or wireless domains. In this paper, we aim to exploit both the wired and wireless domains. Specifically, we consider a fiber-wireless access network in which a passive optical network (PON), consisting of one optical line terminal and multiple optical network units (ONUs), connects densely deployed base stations. In such a scenario, we propose two novel access schemes to utilize both network coding and device association in the following two cases: each device can be associated with one ONU for uploading and downloading its data packets; and each device can be associated with two different ONUs for uploading and downloading its data packets, which are referred to as, the network coding design and symmetric device association (NCsDA) problem and the network coding design and asymmetric device association (NCaDA) problem, respectively. To understand the potentials of NCsDA, we first formulate a mixed integer nonlinear programming to minimize the weighted number of packet transmissions (WNT), which is related to both the energy consumption and system capacity. We then theoretically analyze the tight upper bounds of the minimal WNT in the PON, which helps us to approximate the NCsDA problem by mixed integer linear programming . We also give theoretical analysis on the NCaDA problem and formulate it as a mixed integer linear programming. Next, we develop efficient algorithms based on linear programming relaxation and give network coding designs to solve the NCsDA problem and the NCaDA problem. To validate our design, we conduct extensive simulations, which demonstrate the impact of important network parameters and the promising potentials of the proposed NCsDA and NCaDA schemes.

Energy Efficient Collection Tree Protocol in Wireless Sensor Networks

Objectives: Wireless Sensor Network (WSN) is a collection of sensor nodes which have limited resources like storage and power. To make the network energy efficient, data fusion becomes essential for reducing the number of transmissions. In this paper, we have implemented a data aggregated collection tree protocol (DA-CTP), an enhanced Collection Tree Protocol (CTP) and we compare its performance with the traditional CTP. Methods/Statistical Analysis: For every set of source nodes, the node at the next level will act as an aggregator to accept the packets from source nodes. The function of the aggregator is twofold. If the data packets sent by the source nodes are redundant, the average will be computed on the received data packets and sent to the destination, besides the received data packets will be merged to a single packet. Thereby minimizing the number of packet transmissions. Findings: Our experimental analysis shows that the DA-CTP consumes less energy than traditional CTP without any performance degradation. Application/Improvements: Betweenness Centrality concept can be introduced to minimize the latency.

An Efficient Broadcasting Scheme in Mobile Ad-Hoc Networks

Information broadcasting in MANETs is an essential building block for cooperative operations, group discussions, and common announcements (e.g., filling routing tables). The flooding is the simplest broadcasting scheme used in MANETs. In this scheme, source nodes broadcast at once packets to all neighbors. Broadcasting through flooding causes increased messages redundancy, collision, and wastage of bandwidth and energy. Several approaches have been proposed to solve these issues and could be classified into two main categories: static schemes and adaptive schemes. In this paper, we introduce an adaptive scheme for information broadcasting in MANETs. This scheme allows nodes to select an appropriate action, either to rebroadcast or to discard receiving messages. The decision is based on the amount and timestamps of received messages. Simulations have been conducted and results show that the proposed scheme reduces the number of packet transmissions, has better latency and SRB, good reachability, and low energy consumption.

Joint Channel Assignment and Routing Protocol for Cognitive Radio Ad Hoc Networks

Conventional single channel wireless ad hoc networks usually suffer from low network throughput owing to the higher number of packet transmissions required for multi-hop communication. Using multiple channels within a single network can improve the network throughput. In multi-channel communication networks, the channels must be assigned appropriately to maximise network performance. Existing channel assignment methods are usually based on the approach of interference reduction/minimisation, for example, by making a link to operate on only one channel and different links to operate on different channels. In this paper, we go in the opposite direction and propose to make links to operate on more channels. A new distributed joint channel assignment and routing protocol for cognitive radio ad hoc networks called cognitive radio-enhanced AOMDV is proposed. Simulation studies showed that our method outperforms other methods.

Optimal Stochastic Policies in a Network Coding Capable Ad Hoc Networks

Network coding is a promising technology that increases system throughput by reducing the number of packet transmissions from the source node to the destination node in a saturated traffic scenario. Nevertheless, some packets can suffer from end-to-end delay, because of a queuing delay in an intermediate node waiting for other packets to be encoded with exclusive or (XOR). In this paper, we analyze the delay according to packet arrival rate and propose two network coding schemes, iXOR (Intelligent XOR) and oXOR (Optimal XOR) with Markov Decision Process (MDP). They reduce the average delay, even under an unsaturated traffic load, through the Holding-χ strategy. In particular, we are interested in the unsaturated network scenario. The unsaturated network is more practical because, in a real wireless network, nodes do not always have packets waiting to be sent. Through analysis and extensive simulations, we show that iXOR and oXOR are better than the Distributed Coordination Function (DCF) without XOR (the general forwarding scheme) and XOR with DCF with respect to average delay as well as delivery ratio.

Opportunistic Delayed Transmission for Network Coding in Vehicular Wireless Networks

In vehicular wireless networks, mobile nodes move at a high speed. Thus, the network topology changes frequently. When the traffic is heavy, the collision probability increases dramatically. Network coding is one of the efficient packet transmission schemes to improve throughput and reduce the number of packet transmission. In this paper, we propose an Opportunistic Delayed Transmission (ODT) scheme. This scheme is a trade-off between delay and coding opportunity where the intermediate node may wait for a certain period to maximize the coding opportunity. We use NS-2 network simulator to evaluate the performance of the proposed scheme. The simulation results show that our proposed scheme improves not only the coding ratio but also the packet delivery ratio.

A Novel Mesh Routing Using the Nodes with Identical Tree Level

Contemporary wireless sensor network (WSN) adopts IEEE 802.15.4 in its MAC and PHY layers. The mesh routing introduced in IEEE 802.15.5 standard, referred to as the basic mesh routing below, improves reliability and robustness of routing in WSNs since there are multiple routes from a node to the sink. In this paper, the mesh routing with identical level (MRIL) is proposed, which constructs the mesh using the tree generated per IEEE 802.15.5 standard, the two-hop neighbors of the nodes, and the nodes in the same level chains with each consisting of the nodes having identical tree level. The MRIL outperforms the basic mesh routing in terms of energy consumption, the average number of hops traversed per packet, the sizes of memory used to keep neighbor lists and connectivity matrices at nodes, and the number of packet transmissions in exchanging link state information.

Energy-efficient cache node placement using genetic algorithm in wireless sensor networks

Wireless sensor network (WSN) applications are required to report events and service queries with minimum delay and minimal energy consumption. The network lifetime of a WSN can be extended if the amount of communication in the network is reduced. We can achieve this by caching useful data closer to the requesting node. Caching successfully reduces data access latency and also the number of packet transmissions in the network, thereby increasing network lifetime. However, the important aspect of caching schemes is to identify nodes that can implement caching decisions and also place such cache nodes in a way that they can provide services to as many sensor nodes as possible in their vicinity. This has led to the study of optimal deployment of these cache nodes in a WSN. We carried out experiments to demonstrate the use of a multi-objective genetic algorithm (GA) for cache node placement in a WSN. In this paper, GA optimization aims to increase two parameters: sensors per cache in charge and field coverage. We also show that the GA successfully helps in selecting sensor nodes to implement caching and request forwarding decisions. Finally, we run the Scaled Power Community Index Cooperative Caching scheme (scaPCICC) on the optimized network and compare the delay and total number of overhead messages in the network. We conclude that by reducing the number of messages in the network and reducing the data access latency, the energy consumption of the network is reduced and network lifetime is increased. The experiments were run on MATLAB and ns2.

TCAR: A new network coding-aware routing mechanism based on local topology detection

Recent researches show that inter-session network coding could decrease the number of packets transmission and achieve higher throughput in wireless network compared with traditional forwarding mechanism. In most existing relay mechanisms based on inter-session network such as COPE, relay node demands to collect the messages from its neighbor nodes to get notice of which packets already overheard by them so as to determine whether there exists coding opportunity between or among forwarding packets. However, transmission overhead of this message collection and computing cost of opportunity determination will degrade the performance of these mechanisms. It is observed that coding opportunity at relay node is much more related with the local topology, and the opportunity of encoding three or more packets together is far less than that of encoding two packets together in wireless network with general density. Based on this, a new coding-aware routing mechanism, named TCAR, is proposed. TCAR ignores the opportunity of encoding three or more than three packets together. Each relay node maintains an encoding mapping table being established according to the result of its local topology detection, which can be used to calculate the path cost during routing setup phase, and determine that which two packets can be encoded together during the packets forwarding phase. In TCAR, instead of periodic messages collection, each relay nodes just need once local topology detection, and the encoding determination is much simpler than that of the former mechanisms. Simulation results show that compared with typical inter-session network coding mechanisms COPE and COPE-based routing, TCAR achieves 12% and 7% throughput gains, and keeps the minimum end to end delay.

A Packet Aggregation Mechanism For Real Time Applications Over Wireless Networks

This work presents a packet aggregation technique, named Holding Time Aggregation - HTA. HTA is tailored for real time applications whose data is carried over wireless network environments. At the center of HTA lies an elaborated packet holding time estimation, which makes HTA to be highly adaptable to the diverse link conditions of a wireless setting. Contrary to other proposals that consider fixed packet retention time, the proposed HTA uses an adaptable packet retention time to allow relay nodes to explore aggregation opportunities on a multi-hop path. The proposed mechanism was evaluated and compared to another prominent packet aggregation scheme. Simulation results have shown that the proposed mechanism is capable to keep jitter and total delay within application limits. Furthermore, HTA has shown to allow for substantial reduction on the number of packet transmissions as well as on the overall packet overhead. Savings in terms of packet transmissions reached nearly 80% in the evaluated scenarios. These results have shown that the proposed scheme is able to cope with varying network link capacity and strict application timing requirements. The empirical results have shown to be consistent with the analytical results.

Batch Sliding Window Based-Transmission Coordination Mechanism for Opportunistic Routing

Transmission coordination mechanism (TCM) aids opportunistic routing (OR) to reduce the total number of packet transmissions and improve end-to-end throughput. Existing paradigms based on batch map partitions packets of communication session into segments, and transmit packet segments in batch mode sequentially. However, the rate of successful transmission coordination oscillates due to the oscillation of the number of packets batch transmitted. In this paper, we propose batch sliding window-based TCM to improve the performance of OR. By transmitting packets in continuous batch mode, batch sliding window-based TCM can hold the rate of successful transmission coordination steady. Simulation results show the average end-to-end throughput gain of the proposed TCM is 15.4% over existing batch map-based TCM.

McTorrent: Using multiple communication channels for efficient bulk data dissemination in wireless sensor networks

This paper presents McTorrent, a reliable bulk data dissemination protocol for sensor networks. The protocol is designed to take advantage of multiple radio channels to reduce packet collisions and improve the latency of large object dissemination. We evaluated the performance of McTorrent via detailed simulations and experiments based upon an implementation on the TinyOS platform. Our results show that in comparison to Deluge, the de facto network reprogramming protocol for TinyOS, McTorrent significantly reduces the number of packet transmissions and the amount of time required to propagate a large data object through a sensor network.

Efficiency of the GSM-GPRS Air Interface for Real-Time IP Traffic Flows With and Without Packet Dropping

One IP terminal can occupy a single slot or a multiple number of slots within time frames in the GSM and GPRS, respectively. A limited number of radio resources (slots) are allocated in a base station for such IP terminals. If one IP terminal can occupy only one slot discontinuously in a time frame, there is one possibility resorting to all IP terminals to preserve active mode at a time. Thus, the number of accepted call in the GSM is the same as that of the radio resource. Similarly, if one terminal can occupy a multiple number of slots discontinuously/dynamically in a time frame, the number of accepted calls is obtained by dividing the number of radio resources during that time by the maximum allowed number of slots per IP terminal. A burstiness factor is defined for the IP traffic over GSM-GPRS air interface. Traffic channel efficiency with a bursty real-time IP traffic is unacceptably low, especially with the range of acceptable call loss probabilities pertaining to a lower burstiness factor. The channel efficiency can be enhanced and the call loss probability can be suppressed significantly if a higher maximum number of calls is accepted. Allocated radio resources are less than the maximum number of packet transmissions at a time. Therefore, some packets could be dropped from the real-time transmission system. A complete analysis for the real-time IP packet transmission over the single slot GSM and dynamically variable multislot GPRS air interface without packet dropping, and with packet dropping that increases the channel efficiency is executed. Results show that the channel efficiency as well as the packet dropping probability increases with increasing call intensity, maximum number of admitted IP calls and the burstiness factor.

Cyclic best-effort multicasting with FEC

Cyclic best-effort multicast supports reliable multicast transport by sending information repeatedly. The authors present forward error correcting (FEC) cyclic best-effort multicast which transmits FEC encoded redundant data as well as original data. FEC cyclic multicasting reduces the number of packet transmissions at least by half compared to plain cyclic multicasting.