Article

Identifying Design Requirements for Wireless Routing Link Metrics

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Abstract

In this paper, we identify and analyze the requirements to design a new routing link metric for wireless multihop networks. Considering these requirements, when a link metric is proposed, then both the design and implementation of the link metric with a routing protocol become easy. Secondly, the underlying network issues can easily be tackled. Thirdly, an appreciable performance of the network is guaranteed. Along with the existing implementation of three link metrics Expected Transmission Count (ETX), Minimum Delay (MD), and Minimum Loss (ML), we implement inverse ETX; invETX with Optimized Link State Routing (OLSR) using NS-2.34. The simulation results show that how the computational burden of a metric degrades the performance of the respective protocol and how a metric has to trade-off between different performance parameters.

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... For example, a metric may/can produce computational overhead and it may also pay cost in terms of other performance metric(s) like achieving minimized end-to-end delay at the cost lower throughput or higher routing overhead. Thus, we analyze/investigate almost all possible design requirements given in [7]. In this paper, we present a mathematical framework for a proposed quality link metric; Bandwidth adjusted Inverse ETX (BIETX). ...
... d exp firstly detects and then handles asymmetry by incorporating loss ratios in forward and reverse directions. Computation of d exp , by taking the product of delivery ratios same as in [7] and [12] leads to avoidance of computational overhead that is generated due to ETX which firstly calculates inverse of all expected delivery ratios and then adds them up. There are two techniques to measure L cap i.e., packet-pair with different size and back-to-back probes with equal size. ...
... From [7], we conclude that routing load is an important issue in SWMhNs and this issue becomes critical whenever the network load increases with increase in either the number of packets or the number of nodes. In OLSR, shortest interval has been used for exchanging topological information in comparison to Destination Sequence Distance Vector (DSDV) and Fish-eye State Routing (FSR) [14] i.e., IntraScopeInterval in FSR and 'full-dump-period' in DSDV are equal to 15s, and, T C IN T ERV AL = 5s in OLSR, resulting in the generation of more routing overhead. ...
Conference Paper
In this work, we propose a novel quality link metric; Bandwidth adjusted Inverse ETX (BIETX) for Static Wireless Multi-hop Networks (SWMhNs). The proposed metric considers two path selection parameters into account i.e., packet delivery ratio and link capacity. For computing packet delivery ratios in BIETX, the mechanism of Expected Transmission Count (ETX) is adopted. On the other hand, we take two methods of computing link capacity in BIETX. These methods are based upon the size of pair probes; equal size and different size. We also enhance Optimized Link State Routing (OLSR) protocol while using BIETX. A comparative analysis of proposed metric with equal size and different size pair probe; BIETX-1 and BIETX-2, with two existing quality metrics (ETX and Expected Transmission Time (ETT)) in SWMhNs is also a part of this work. From simulation results, we conclude that BIETX-2 outperforms rest of the metrics because of low routing load in ad-hoc probes, and low routing latencies due to enhancements of routing update frequencies and window size in OLSR.
... Several QLMs have been proposed, like, Expected Transmission Count (ETX)[2], Expected Transmission Time (ETT) [3], Interference and Bandwidth Adjusted ETX (IBETX) [4], Expected Link Performance (ELP) [5], Minimum Loss (ML) [6], Minimum Delay (MD)[7] and Inverse ETX (InvETX) [8]. The metrics, ETX, ML, MD and InvETX have already been implemented [8] with a proactive routing protocol, Optimized Link State Routing (OLSR) [9] using Link State routing technique . ...
... Several QLMs have been proposed, like, Expected Transmission Count (ETX)[2], Expected Transmission Time (ETT) [3], Interference and Bandwidth Adjusted ETX (IBETX) [4], Expected Link Performance (ELP) [5], Minimum Loss (ML) [6], Minimum Delay (MD)[7] and Inverse ETX (InvETX) [8]. The metrics, ETX, ML, MD and InvETX have already been implemented [8] with a proactive routing protocol, Optimized Link State Routing (OLSR) [9] using Link State routing technique . While, ETX, IBETX, and ELP are implemented with Destination Sequenced Distance Vector (DSDV) [10] based on distance vector routing algorithm. ...
... Previouse implementation of QLMs in routing protocols have not considered routing load for performance measurements. We, in our previous work [8] have considered routing load while analyzing the performance of OLSR which is a link state based proactive routing protocol. Now, in the same way, we are evaluating the performance of those link metrics along with ETT in this paper. ...
Article
Full-text available
In this paper, we compare and analyze performance of five quality link metrics forWireless Multi-hop Networks (WMhNs). The metrics are based on loss probability measurements; ETX, ETT, InvETX, ML and MD, in a distance vector routing protocol; DSDV. Among these selected metrics, we have implemented ML, MD, InvETX and ETT in DSDV which are previously implemented with different protocols; ML, MD, InvETX are implemented with OLSR, while ETT is implemented in MR-LQSR. For our comparison, we have selected Throughput, Normalized Routing Load (NRL) and End-to-End Delay (E2ED) as performance parameters. Finally, we deduce that InvETX due to low computational burden and link asymmetry measurement outperforms among all metrics.
... Several QLMs have been proposed, like, Expected Transmission Count (ETX)[2], Expected Transmission Time (ETT) [3], Interference and Bandwidth Adjusted ETX (IBETX) [4], Expected Link Performance (ELP) [5], Minimum Loss (ML) [6], Minimum Delay (MD)[7] and Inverse ETX (InvETX) [8]. The metrics, ETX, ML, MD and InvETX have already been implemented [8] with a proactive routing protocol, Optimized Link State Routing (OLSR) [9] using Link State routing technique . ...
... Several QLMs have been proposed, like, Expected Transmission Count (ETX)[2], Expected Transmission Time (ETT) [3], Interference and Bandwidth Adjusted ETX (IBETX) [4], Expected Link Performance (ELP) [5], Minimum Loss (ML) [6], Minimum Delay (MD)[7] and Inverse ETX (InvETX) [8]. The metrics, ETX, ML, MD and InvETX have already been implemented [8] with a proactive routing protocol, Optimized Link State Routing (OLSR) [9] using Link State routing technique . While, ETX, IBETX, and ELP are implemented with Destination Sequenced Distance Vector (DSDV) [10] based on distance vector routing algorithm. ...
... Previouse implementation of QLMs in routing protocols have not considered routing load for performance measurements. We, in our previous work [8] have considered routing load while analyzing the performance of OLSR which is a link state based proactive routing protocol. Now, in the same way, we are evaluating the performance of those link metrics along with ETT in this paper. ...
... An efficiently designed QLM better helps a routing protocol to achieve appreciable performance by dealing with these issues. In our previous work[1], design requirements of QLM are discussed in detail. Moreover, a new QLM; InvETX, is also compared with Expected Transmission Count (ETX)[2], Minimum Loss (ML) and Minimum Delay (MD)[4]in Optimized Link State Routing (OLSR)[5]protocol. ...
... For example, a routing protocol achieves higher throughput at the cost of end-to-end delay or routing overhead. Therefore, we analyze possible design requirements in[1]. Further, in our previous work, we implement three existing link metrics; ETX, MD,and ML, and one newly proposed metric; InvETX OLSR using NS-2.34. ...
... As a result, InvET X achieves higher throughputs than M L and ET X. Similarly, M L performs better than ET X. From[1], we analyze that routing load is a critical issue in SWMhNs when network load increases either with increase in number of nodes or with increase in number of packets. As, OLSR uses the shortest interval for exchanging topological information as compared to DSDV, i.e., 'full-dump-period' in DSDV, whereas, in OLSR T C IN T ERV AL = 5s, therefore, it causes more routing overhead. ...
Article
In this paper, we propose a new Quality Link Metric (QLM), ``Inverse Expected Transmission Count (InvETX)'' in Optimized Link State Routing (OLSR) protocol. Then we compare performance of three existing QLMs which are based on loss probability measurements; Expected Transmission Count (ETX), Minimum Delay (MD), Minimum Loss (ML) in Static Wireless Multi-hop Networks (SWMhNs). A novel contribution of this paper is enhancement in conventional OLSR to achieve high efficiency in terms of optimized routing load and routing latency. For this purpose, first we present a mathematical framework, and then to validate this frame work, we select three performance parameters to simulate default and enhanced versions of OLSR. Three chosen performance parameters are; throughput, Normalized Routing Load and End-to-End Delay. From simulation results, we conclude that adjusting the frequencies of topological information exchange results in high efficiency.
... This issue is especially challenging as these networks are built to work in specific scenarios. For example, a monitoring network can require a reasonable level of Packet Delivery Ratio (PDR) [8,9]. On the other hand, when the goal is to enable a VoIP (Voice over Internet Protocol) content, the network needs to keep under control the Endto-End Delay (E2ED) [8,9]. ...
... For example, a monitoring network can require a reasonable level of Packet Delivery Ratio (PDR) [8,9]. On the other hand, when the goal is to enable a VoIP (Voice over Internet Protocol) content, the network needs to keep under control the Endto-End Delay (E2ED) [8,9]. Therefore, distinct applications can demand different Quality of Service (QoS) guarantees [6,[10][11][12]. ...
... In this light, the routing protocols should also consider the different applications can have conflicting quality requirements. As a result, future routing mechanisms must support two or more QoS requirements and take into account the trade-off between them, since state-of-the-art protocols do not have these features natively [9,13]. ...
Article
Full-text available
Ad hoc wireless networks have aroused much interest of the scientific community in the last two decades. The provision of Quality of Service (QoS) is a prominent challenge in this research field, since these networks are prone to suffer from instabilities related to wireless medium and mobility. Depending on application, the protocol needs to consider two or more QoS criteria when solving the routing problem. In this context, this work proposes a multicriteria and adaptive framework for proactive routing in order to generate promising compromise solutions by considering critical network quality indicators. Two new methods are proposed—one based on weighted sum method and another based on compromise method (\(\varepsilon\)-constraint)—and compared with the standard weighted sum method. Aiming to map a single final solution, a utility function is proposed to support the definition of the parameters (weights and constraints) of each method. The results show the framework, jointly with the proposed methods, were efficient in promoting significant improvements in the quality indicators investigated in static and mobile scenarios.
... An efficiently designed QLM better helps a routing protocol to achieve appreciable performance by dealing with these issues. In our previous work [1], design requirements of QLM are discussed in detail. Moreover, a new QLM, Inverse Expected Transmission Count (InvETX), is also compared with Expected Transmission Count (ETX) [2], Minimum Loss (ML) [3], and Minimum Delay (MD) [4] in Optimized Link State Routing (OLSR) [5] protocol. ...
... achieving high packet delivery ratio on the cost of increased end-to-end delay). Therefore, we analyze almost all possible design requirements in [1]. Further, in our previous work, we implement three existing link metrics, ETX, MD,and ML, and one newly proposed metric, InvETX OLSR, using NS-2.34. ...
... The maximum reachability of a node belonging to Minimizing Longer path increases routing (1) By minimizing the number of transmi- Hop count [14] path length latency and reduces throughssions and (2) path selection with miniput of a path mum loss rates or higher probabilities of successful transmissions, etc. Balancing traffic Overloaded traffic causes drop Divert traffic from congested path or Transmission load rate due to congestion overloaded nodes to underloaded or reduction [15] idle ones Minimizing delay Delay results time-out buffer Delay can be reduced with selection ETX [15], [14], per of a path having minimum intraflow hop RTT, [11] per and interflow interferences along with hop PktPair [11] queuing delays and maximum link capacity ML [3] Maximizing networks capacity directly effects (1) Minimize interferences or retransmissions, MIC [14] aggregating throughput and (2) allow the multiple bandwidth rates to coexist in a network where a higher channel rate is used over each link Minimizing energy A path with an unreliable Reduction in retransmissions during MTPR [17], consumption link produces longer delay due routing to optimize communication delay MBCR [18] to higher retransmission rates and ultimately results in an increase in energy consumption Minimizing channel/ Data flow switching on different Interface assignment strategy keeps MIC [14], interface switching channels results in delay one interface fixed on a specific channel, WCETT [14] while other interfaces can be switched among the remaining channels; when necessary, Minimizing the Computational overhead consumes computations should be considered InvETX [1] computational memory, processing capability, that must not consume memory, processing overhead and battery power capability, and, most importantly, battery power Minimizing Intraflow and interflow interferences During path calculation, capture diversity MCR protocol interference result in bandwidth starvation of channel assignments and link capacity [14] and [14] Maximizing Instability in path weight results Load sensitivity or topology- Link affinity metric [19] route stability in drop rates dependent metrics solve instability issues with MCMR [20] Maximizing Faulty routes cause drop rates This problem can be solved through wireless ad hoc fault tolerance/ in high network flows providing redundant information of network [21] minimizing route alternative paths sensitivity Avoiding short-and Redundant links due to short- (1) Minimum TTL value that eliminates OLSR in long-lived and long-lived loops resulted in mini-loops [16]; (2) fresh sequence sparse WMNs [16] loops more path lengths and consequently number, etc. quently increased E2ED Considering E2ED in static networks cause A suitable trade-off helps to increase ML [3] performance drop rate efficiency trade-offs Also, the MPR(u) set of a node (u), a subset of H 1 (u), can be defined as follows: ...
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In this paper, we propose a new Quality Link Metric (QLM), “Inverse Expected Transmission Count (InvETX),” in Optimized Link State Routing (OLSR) protocol. Then, we compare performance of three existing QLMs which are based on loss probability measurements: Expected Transmission Count (ETX), Minimum Delay (MD), and Minimum Loss (ML) in Static Wireless Multihop Networks (SWMhNs). A novel contribution of this paper is enhancement in conventional OLSR to achieve high efficiency in terms of optimized routing load and routing latency. For this purpose, first we present a mathematical framework, and then to validate this frame work, we select three performance parameters to simulate default and enhanced versions of OLSR. The three chosen performance parameters are throughput, Normalized Routing Load, and End-to-End Delay. From the simulation results, we conclude that adjusting the frequencies of topological information exchange results in high efficiency.
... Besides the evaluating the performance of DSDV, OLSR and DYMO we also made some modifications to these routing protocols and observed their performance at the end we came up with the result that with minor. In future, we are interested to apply the same analysis on quality link metrics proposed in9101112 and at MAC layer as [13, 14]. ...
Article
In this paper, we present path loss model for VANETs and simulate three routing protocols; Destination Sequenced Distance Vector (DSDV), Optimized Link State Routing (OLSR) and Dynamic MANET On-demand (DYMO) to evaluate and compare their performance using NS-2. The main contribution of this work is enhancement of existing techniques to achieve high efficiency of the underlying networks. After extensive simulations in NS-2, we conclude that DSDV best performs with 802.11p while DYMO gives outstanding performance with 802.11.
... On the other hand in MOD DSR due to reduction in the size of route. In future work, we are interested to implement Expected Transmission Count (ETX) link metric with mathematical modeling, as demonstrated in111213. ...
Article
In this paper, a framework is presented for node distribution with respect to density, network connectivity and communication time. According to modeled framework we evaluate and compare the performance of three routing protocols; Ad-hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Fisheye State Routing (FSR) in MANETs and VANETs using two Mac-layer protocols; 802.11 and 802.11p. We have further modified these protocols by changing their routing information exchange intervals; MOD AODV, MOD DSR and MOD FSR. A comprehensive simulation work is performed in NS-2 for the comparison of these routing protocols for varying mobilities and scalabilities of nodes. To evaluate their efficiency; throughput, End-to-End Delay (E2ED) and Normalized Routing Load (NRL) of these protocols are taken into account as performance parameters. After extensive simulations, we observe that AODV outperforms both with MANETs and VANETs.
... In future, we will implement different performance metrics of AM-DisCNT, as authors have done in [17], [18], [19] and [20]. ...
Article
The nodes in wireless sensor networks (WSNs) contain limited energy resources, which are needed to transmit data to base station (BS). Routing protocols are designed to reduce the energy consumption. Clustering algorithms are best in this aspect. Such clustering algorithms increase the stability and lifetime of the network. However, every routing protocol is not suitable for heterogeneous environments. AM-DisCNT is proposed and evaluated as a new energy efficient protocol for wireless sensor networks. AM-DisCNT uses circular deployment for even consumption of energy in entire wireless sensor network. Cluster-head selection is on the basis of energy. Highest energy node becomes CH for that round. Energy is again compared in the next round to check the highest energy node of that round. The simulation results show that AM-DisCNT performs better than the existing heterogeneous protocols on the basis of network lifetime, throughput and stability of the system.
... Future work focuses on estimating the delay in propagating data from body sensors to the destination node in DARE protocol and also to investigate mobility in patients body. Authors in [20][21][22][23], work on routing metrics based on ETX (Expected Transmission Count) which, shows better performance than minimum hop count metric, under the availability of link. In view of this, the plan focus to work on routing link metrics as well. ...
Article
In recent years, interests in the applications of Wireless Body Area Sensor Network (WBASN) is noticeably developed. WBASN is playing a significant role to get the real time and precise data with reduced level of energy consumption. It comprises of tiny, lightweight and energy restricted sensors, placed in/on the human body, to monitor any ambiguity in body organs and measure various biomedical parameters. In this study, a protocol named Distance Aware Relaying Energy-efficient (DARE) to monitor patients in multi-hop Body Area Sensor Networks (BASNs) is proposed. The protocol operates by investigating the ward of a hospital comprising of eight patients, under different topologies by positioning the sink at different locations or making it static or mobile. Seven sensors are attached to each patient, measuring different parameters of Electrocardiogram (ECG), pulse rate, heart rate, temperature level, glucose level, toxins level and motion. To reduce the energy consumption, these sensors communicate with the sink via an on-body relay, affixed on the chest of each patient. The body relay possesses higher energy resources as compared to the body sensors as, they perform aggregation and relaying of data to the sink node. A comparison is also conducted conducted with another protocol of BAN named, Mobility-supporting Adaptive Threshold-based Thermal-aware Energy-efficient Multi-hop ProTocol (M-ATTEMPT). The simulation results show that, the proposed protocol achieves increased network lifetime and efficiently reduces the energy consumption, in relative to M-ATTEMPT protocol.
... Because, a link metric provides all available end-to-end paths and the best path information to the respective protocol. So, in future, we are interested to develop a new link metric, like [21] and [22]. ...
Article
Full-text available
This paper evaluates and compares the performance of two routing protocols, one is reactive, Dynamic MANET On-Demand (DYMO) and other is proactive, Optimized Link State Routing (OLSR) in Mobile Ad-hoc Networks (MANETs) and Vehicular Ad-hoc Networks (VANETs). Performance of these protocols is analyzed using three performance metrics; Packet Delivery Ratio, Normalized Routing Overhead and End-to-End Delay against varying scalabilities of nodes. We perform these simulations with NS-2 using TwoRayGround propagation model. The SUMO simulator is used to generate a random mobility pattern for VANETs. From the extensive simulations, we observe that DYMO performs better than OLSR for both VANETs and MANETs at the cost of delay. Moreover, DYMO performs better in VANETs as compared to MANETs.
... In future, Routing Link Matrices can also be applied on this proposed technique. Routing can be done by adapting many different approaches as done in [14], [15] and [16]. Application of Routing Link Matrices on the proposed scheme can be useful in achieving efficient consumption of energy in the network. ...
Article
In this paper, we propose Regional Energy Efficient Cluster Heads based on Maximum Energy (REECH-ME) Routing Protocol for Wireless Sensor Networks (WSNs) . The main purpose of this protocol is to improve the network lifetime and particularly the stability period of the network. In REECH-ME, the node with the maximum energy in a region becomes Cluster Head (CH) of that region for that particular round and the number of the cluster heads in each round remains the same. Our technique outperforms LEACH which uses probabilistic approach for the selection of CHs. We also implement the Uniform Random Distribution Model to find the packet drop to make this protocol more practical. We also calculate the confidence interval of all our results which helps us to visualize the possible deviation of our graphs from the mean value.
... In future, Routing Link Matrices can also be applied on this proposed technique. Routing can be done by adapting many different approaches as done in[14],[15]and[16]. Application of Routing Link Matrices on the proposed scheme can be useful in achieving efficient consumption of energy in the network. ...
Article
Full-text available
In this paper, we propose Regional Energy Efficient Cluster Heads based on Maximum Energy (REECH-ME) Routing Protocol for Wireless Sensor Networks (WSNs). The main purpose of this protocol is to improve the network lifetime and particularly the stability period of the network. In REECH-ME, the node with the maximum energy in a region becomes Cluster Head (CH) of that region for that particular round and the number of the cluster heads in each round remains the same. Our technique outperforms LEACH [1] which uses probabilistic approach for the selection of CHs. We also implement the Uniform Random Distribution Model to find the packet drop to make this protocol more practical. We also calculate the confidence interval of all our results which helps us to visualize the possible deviation of our graphs from the mean value.
... In this paper, the scenario we have presented is through the motivation of [24] and [25]. In [26], they have done evaluation of protocols through radio propagation model Nakagami which is well suited for all these models. ...
Article
Full-text available
In this paper, a novel framework is presented through link and path duration for link availability of paths. Further, we evaluate and analyze our work by varying the number of nodes, pause time and speed in VANETs. We select three routing protocols namely Ad-hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Fish-eye State Routing (FSR). Performance of these protocols is analyzed using Packet Delivery Ratio (PDR), Normalized Routing Overhead (NRO), End-to-End Delay (E2ED), Average Link Duration (ALD) and Average Path Duration (APD) against varying scalability, pause time and speed as performance metrices. We perform these simulations with NS-2 implementing Nakagami radio propagation model. The SUMO simulator is used to generate a random mobility pattern for VANETs. To find link duration and path duration we also use MATLAB. From the extensive simulations, we observe that AODV and DSR outperform better among all three routing protocols.
... Hence, THE-FAME gives better results in both energy and delay profiles as compared to multi-hop routing scheme. In future work, we will implement Expected Transmission Count (ETX) link metrics as demonstrated in [21] [22] [23] [24]. ...
Article
Wireless Body Area Sensor Network (WBASN) is a technology employed mainly for patient health monitoring. New research is being done to take the technology to the next level i.e. player's fatigue monitoring in sports. Muscle fatigue is the main cause of player's performance degradation. This type of fatigue can be measured by sensing the accumulation of lactic acid in muscles. Excess of lactic acid makes muscles feel lethargic. Keeping this in mind we propose a protocol \underline{TH}reshold based \underline{E}nergy-efficient \underline{FA}tigue \underline{ME}asurement (THE-FAME) for soccer players using WBASN. In THE-FAME protocol, a composite parameter has been used that consists of a threshold parameter for lactic acid accumulation and a parameter for measuring distance covered by a particular player. When any parameters's value in this composite parameter shows an increase beyond threshold, the players is declared to be in a fatigue state. The size of battery and sensor should be very small for the sake of players' best performance. These sensor nodes, implanted inside player's body, are made energy efficient by using multiple sinks instead of a single sink. Matlab simulation results show the effectiveness of THE-FAME.
... Giving measurable QoS ensures a viable data transfer capacity. Similarly, on observing the patterns on how the Internet has transformed people lives by trading various types of data among countless customers, WSNs may sooner rather than later be similarly emerge to be critical players by providing data about the physical wonders of intrigue and eventually having the option to recognise and control them to develop increasingly precise models of the physical world [8][9][10]. This is due to the fact that WSNs are completely different from traditional systems in this regard. ...
Article
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Quality of Service (QoS) in Wireless Sensor Networks (WSN) are contemplated as one on the major attributes in evaluating the overall efficiency of them. Some of the qualities of WSNs include incredibly asset compelled sensors, irregular arrangement of sensors in the scene of deployment, novel information driven correspondence conventions that presents remarkable challenges in the improvement of Quality of Service support in Wireless Sensor Networks. The appropriation of WSN by applications require complex tasks that extends from human services to mechanical checking that are necessary for a wide range of day-to-day and remote applications. WSN has increased a lot of consideration in the present exploration for supporting a wide assortment of utilizations including the interactive media applications. Interactive media applications that are proposed are viewed as delay-sensitive and time-critical applications and require enough vitality and correspondence assets. The proposed QoS-dependent and varied clustered routing (QoS–VCR) algorithm preserves the vitality in the system.
... Our simulation results shows that proposed routing scheme enhance the network stability time and packet delivered to sink. Path loss is also investigated in this protocol and in future work, we will implement Expected Transmission Count (ETX) link metrics as demonstrated in [22] [23] [24]. ...
Article
In this work, we propose a reliable, power efficient and high throughput routing protocol for Wireless Body Area Networks (WBANs). We use multi-hop topology to achieve minimum energy consumption and longer network lifetime. We propose a cost function to select parent node or forwarder. Proposed cost function selects a parent node which has high residual energy and minimum distance to sink. Residual energy parameter balances the energy consumption among the sensor nodes while distance parameter ensures successful packet delivery to sink. Simulation results show that our proposed protocol maximize the network stability period and nodes stay alive for longer period. Longer stability period contributes high packet delivery to sink which is major interest for continuous patient monitoring.
... These metrics trade-off between different performance parameters, the computational burden of some metrics also degrades the performance of the respective protocol [9]. Considering that the functionality of SG is dependent on the ability of different applications meeting certain performance requirements, proposing multiple metric implemented within the existing routing protocols can guarantee the QoS of the variety of traffic in SG AMI network. ...
Conference Paper
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Routing in Neighbourhood Area Network (NAN) for Smart Grid's Advanced Metering Infrastructure (AMI) raises the need for Quality of Service (QoS)-Aware routing. This is due to the expanded list of applications that will result in the transmission of different types of traffic between NAN devices (i.e smart meters). In wireless mesh network (WMN) routing, a combination of multiple link metrics, though complex, has been identified as a possible solution for QoS routing. These complexities (i.e Np complete problem) can be resolved through the use of Analytical Hierarchy Process (AHP) algorithm and pruning techniques. With the assumption that smart meters transmit IP packets of different sizes at different interval to represent AMI traffic, a case study of the performance of three Optimised Link State Routing (OLSR) link metrics is carried out on a grid topology NAN based WMN in ns-2 network simulator. The best two performing metric were used to show the possibility of combining multiple metrics with OLSR through the AHP algorithm to fulfill the QoS routing requirements of targeted AMI application traffic in NANs.
... Koksal et al. [5] presented a modified ETX metric, which combined the average and the variability of the error probability to optimize the decision results. Javaid et al. [6] presented a comprehensive study on the design requirements for routing link metrics and an inverse ETX (invETX) link metric for wireless multi-hop networks. In Boushaba et al. [7], considered the packet loss, intraflow and interflow interference, and load at gateways to select the best paths to reach the selected gateways and present a novel source-based routing (SBR) metric method. ...
Article
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The routing protocol is one of the most important aspects of the wireless sensor network, determining network connectivity, delay, energy balancing, reliability and other factors. Furthermore, a minimum hop-count does not mean minimum delay and energy consumption. To overcome the routing protocol’s shortcomings, we proposed an energy-efficient expected transmission count routing decision strategy (E³TX) for wireless sensor networks. E³TX makes use of two physical parameters, received signal strength indicator (RSSI) and battery voltage, to obtain the final decision via our proposed decision strategy. In our strategy, the received signal strength indicator is used to predict the future packet reception rate (PRR), and the battery voltage is used to estimate the residual energy of network nodes to balance their load. In order to estimate the packet reception rate via the received signal strength indicator with greater accuracy, we performed multiple experiments to build the relationship model between RSSI and PRR. In this article, we use NS-2.35 to evaluate and compare the performance of E³TX with AODV, AOMDV and BIETX. Our simulation results show that our proposed E³TX performs well when compared to the previous studies, not only in terms of energy consumption, but also in reliable data transmission and end-to-end delay.
... On the other hand in MOD DSR due to reduction in the size of route cache improves overall performance in high speeds. In future, we are interested to apply the same analysis on quality link metrics proposed in101112 and at MAC layer as [13, 14]. a. MANET's NRL vs Scalibility b. ...
Article
This paper presents a framework for node distribution with respect to density, network connectivity and communication time. Using NS2, we evaluate and compare performance of three routing protocols; Ad-hoc On-demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Fisheye State Routing (FSR) both in MANETs (IEEE 802.11) and VANETs (IEEE 802.11p). We further enhanced these protocols by changing their routing information exchange intervals; MOD AODV, MOD DSR and MOD FSR. A comprehensive simulation work is performed for the comparison of these routing protocols for varying motilities and scalabilities of nodes. As a result, we can say that AODV outperforms DSR and FSR both in MANETs and VANETs.
... where En is the initial energy of any of the four energy levels, r is the node at a specific energy level, ET X p is the expected transmission count [42] of a path P , InvET X p is the inverse expected transmission count [43], and MLp is the minimum loss [44]. The P metric values for the hybrid, high, medium, and low energy level nodes are given by Eqs. 19, 20, 21, and 22, respectively. ...
Article
Wireless sensor networks (WSNs) have gained much attention in today’s research domain for supporting a wide variety of applications including the multimedia applications. Multimedia applications that are regarded as the quality-ofservice (QoS)-aware, delay sensitive, and bandwidth hungry applications, require enough energy and communication resources. WSNs being the energy-scarce network have now been designed in such a way that they can support these delay-sensitive and time-critical applications. In this paper, we propose an energyefficient routing protocol for heterogeneous WSNs to support the delay sensitive, bandwidth hungry, time-critical, and QoSaware applications. The proposed QoS-aware and heterogeneously clustered routing (QHCR) protocol not only conserves the energy in the network, but also provides the dedicated paths for the real-time and delay sensitive applications. The inclusion of different energy-levels for the heterogeneous WSNs also provide the stability in the networks while minimizing the delay for the delay-sensitive applications. Extensive simulations have been performed to validate the effectiveness of our proposed scheme. Our proposed routing scheme outperforms other state-of-the-art schemes in terms of the delay performances.
... Because, a link metric provides all available end-to-end paths and the best path information to the respective protocol. So, in future, we are interested to develop a new link metric, like [17] and [18]. ...
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Mobile Ad-hoc NETworks (MANETs) comprise on wireless mobile nodes that are communicating with each other without any infrastructure. Vehicular Ad-hoc NETwork (VANET) is a special type of MANETs in which vehicles with high mobility need to communicate with each other. In this paper, we present a novel framework for link availability of paths for static as well as dynamic networks. Moreover, we evaluate our frame work for routing protocols performance with different number of nodes in MANETs and in VANETs. We select three routing protocols namely Ad-hoc On-demand Distance Vector (AODV), Fish-eye State Routing (FSR) and Optimized Link State Routing (OLSR). Furthermore, we have also modified default parameters of selected protocols to check their efficiencies. Performance of these protocols is analyzed using three performance metrics; Packet Delivery Ratio (PDR), Normalized Routing Overhead (NRO) and End-to-End Delay (E2ED) against varying scalabilities of nodes. We perform these simulations with NS-2 using TwoRayGround propagation model. The SUMO simulator is used to generate a random mobility pattern for VANETs. From the extensive simulations, we observe that AODV outperforms among all three protocols.
... Performance of the selected protocols are then analysed and compared using the proposed model. In [15], a new routing link metric is designed, and in [16], a new quality link metric called inverse expected transmission count (InvETX) is proposed. The main contribution of [16] is improvement of the optimized link state routing (OLSR) protocol in terms of optimized routing load and routing latency. ...
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One of the most important issues in wireless sensor networks (WSNs) is to reduce energy consumption and increase the network lifetime. Proper election of cluster head is one of the approaches to reduce energy consumption in the network. Among existing methods, low-energy adaptive cluster hierarchy (LEACH) is the most prevalent routing algorithm, in which the cluster head is elected based on a given threshold. In LEACH algorithm, only the cluster heads are allowed to send information to the base station (BS). In this paper, a novel routing protocol based on super cluster head election using fuzzy logic in three levels (SCHFTL) is proposed, in which a super cluster head is elected among the cluster heads. The super cluster head election is performed based on a fuzzy description in three levels using Mamdani inference engine. Effectiveness of the proposed SCHFTL routing protocol is verified through MATLAB simulations in terms of death, time of the first node and network lifetime compared with LEACH, cluster head election mechanism using fuzzy logic (CHEF) and fuzzy-based master cluster head election leach (F-MCHEL) protocols.
... Because, a link metric provides all available end-to-end paths and the best path information to the respective protocol. So, in future, we are interested to develop a new link metric, like [41] and [42]. ...
Thesis
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Mobile Ad-hoc NETworks (MANETs) are comprised of wireless mobile nodes that are communicating with each other without any infrastructure. Vehicular Ad-hoc NETwork (VANET) is a special type of MANETs in which vehicles with high mobility need to communicate with each other. In our project, a framework for link availability for static as well as dynamic network and also experimental parameters in which Packet Delivery Ratio (PDR), effect of link duration over End-to-End Delay (E2ED) and Normalized Routing Overhead (NRO) in terms of control packets is analyzed and modeled for MANETs and VANETs. Moreover, this project also contributes the performance comparison of three reactive routing potocols; Ad-hoc On-Demand Distance Vector (AODV), DYnamic Source Routing (DSR), DYnamic MANET On-Demand (DYMO) and three proactive protocols; Destination Sequenced Distance Vector (DSDV), Fish-eye State Routing (FSR) and Optimized Link State Routing (OLSR). A novel contribution of this work is enhancement of efficiency of these protocols except DSDV. Three performance parameters; PDR, E2ED and NRO with varying scalabilities are measured to analyze performance of the selected protocols both with default and enhanced version. From extensive simulations, it is observed that DSR outperforms both in MANETs and in VANETs at the cost of delay. Moreover, DSR performs better in VANETs as compared to MANETs. The NS-2 is used for simulation with TwoRayGround propagation model. The Simulation of Urban MObility (SUMO) and Vehicular Ad-hoc Networks Mobility Simulator (VanetMobiSim) are used to generate the mobility pattern for VANETs.
... Our simulation results show that DSR performs better at the cost of delay both in MANETs and in VANETs. In future, we are interested to develop a new link metric, like [16] and [17]. ...
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In this paper, a framework for experimental parameters in which Packet Delivery Ratio (PDR), effect of link duration over End-to-End Delay (E2ED) and Normalized Routing Overhead (NRO) in terms of control packets is analyzed and modeled for Mobile Ad-Hoc NETworks (MANETs) and Vehicular Ad-Hoc NETworks (VANETs) with the assumption that nodes (vehicles) are sparsely moving in two different road. Moreover, this paper contributes the performance comparison of one Proactive Routing Protocol; Destination Sequenced Distance vector (DSDV) and two reactive protocols; DYnamic Source Routing (DSR) and DYnamic MANET On-Demand (DYMO). A novel contribution of this work is enhancements in default versions of selected routing protocols. Three performance parameters; PDR, E2ED and NRO with varying scalabilities are measured to analyze the performance of selected routing protocols with their original and enhanced versions. From extensive simulations, it is observed that DSR outperforms among all three protocols at the cost of delay. NS-2 simulator is used for simulation with TwoRayGround propagation model to evaluate analytical results.
... The outcome displays the improved performance as compared to the existing protocol. In future, one can modify this problem statement to implement various link metrics that like ETX link metrics [16,17]. ...
... For delay sensitive applications, DYMO in reactive protocols and OLSR in proactive protocols are the plausible choices. During all this evaluation, we come to realize that the most important component of a routing protocol is routing link metric, so, future we are interested to propose and implement a new ETX-based routing link metric with AODV and OLSR, as discussed in [14], [15], [16]. ...
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... The authors in [16] identify a diversity of possible requirements to be addressed in a MANET, such as: minimizing hop-count, minimizing delay, maximizing data delivery, minimizing energy consumption, minimizing computational overhead, maximizing route stability, balancing traffic load, among others. The work also relates these requirements to the main link evaluation metrics and points out the associated performance trade-offs. ...
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... In this work, we study the three performance metrics: Network lifetime , Residual energy and throughput. In future, we will study ETX link metrics and we will implement this metric in our scheme as implemented and demonstrated in [21] [22] [23]. ...
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In this research work, we advise gateway based energy-efficient routing protocol (M-GEAR) for Wireless Sensor Networks (WSNs). We divide the sensor nodes into four logical regions on the basis of their location in the sensing field. We install Base Station (BS) out of the sensing area and a gateway node at the centre of the sensing area. If the distance of a sensor node from BS or gateway is less than predefined distance threshold, the node uses direct communication. We divide the rest of nodes into two equal regions whose distance is beyond the threshold distance. We select cluster heads (CHs)in each region which are independent of the other region. These CHs are selected on the basis of a probability. We compare performance of our protocol with LEACH (Low Energy Adaptive Clustering Hierarchy). Performance analysis and compared statistic results show that our proposed protocol perform well in terms of energy consumption and network lifetime.
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The Thirteenth International Conference on Wireless and Mobile Communications (ICWMC 2017), held between July 23 - 27, 2017 - Nice, France, followed on the previous events on advanced wireless technologies, wireless networking, and wireless applications. ICWMC 2017 addressed wireless related topics concerning integration of latest technological advances to realize mobile and ubiquitous service environments for advanced applications and services in wireless networks. Mobility and wireless, special services and lessons learnt from particular deployment complemented the traditional wireless topics. We take here the opportunity to warmly thank all the members of the ICWMC 2017 Technical Program Committee, as well as the numerous reviewers. The creation of such a high quality conference program would not have been possible without their involvement. We also kindly thank all the authors who dedicated much of their time and efforts to contribute to ICWMC 2017. We truly believe that, thanks to all these efforts, the final conference program consisted of top quality contributions. Also, this event could not have been a reality without the support of many individuals, organizations, and sponsors. We are grateful to the members of the ICWMC 2017 organizing committee for their help in handling the logistics and for their work to make this professional meeting a success. We hope that ICWMC 2017 was a successful international forum for the exchange of ideas and results between academia and industry and for the promotion of progress in the area of wireless and mobile communications. We are convinced that the participants found the event useful and communications very open. We also hope that Nice provided a pleasant environment during the conference and everyone saved some time for exploring this beautiful city.
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This document describes the Optimized Link State Routing (OLSR) protocol for mobile ad hoc networks. The protocol is an optimization of the classical link state algorithm tailored to the requirements of a mobile wireless LAN. The key concept used in the protocol is that of multipoint relays (MPRs). MPRs are selected nodes which forward broadcast messages during the flooding process. This technique substantially reduces the message overhead as compared to a classical flooding mechanism, where every node retransmits each message when it receives the first copy of the message. In OLSR, link state information is generated only by nodes elected as MPRs. Thus, a second optimization is achieved by minimizing the number of control messages flooded in the network. As a third optimization, an MPR node may chose to report only links between itself and its MPR selectors. Hence, as contrary to the classic link state algorithm, partial link state information is distributed in the network. This information is then used for route calculation. OLSR provides optimal routes (in terms of number of hops). The protocol is particularly suitable for large and dense networks as the technique of MPRs works well in this context.
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The use of Fish eye scoping has been introduced to reduce the overhead of the OLSR routing protocol. This simple method is based on reducing the scope (TTL) of some topology updates, thus giving routers a precise view of their close neighborhood and a more and more approximate view of farther nodes. Fish Eye OLSR (OFLSR) has been showed to have excellent scaling properties and low network overhead. However, if deployed in relatively sparse networks, this scoping limitation of topology updates can result in long living routing loops, thus limiting the potential applications of such mechanisms in some practical wireless mesh networks. In this paper, we address the transient mini-loop problem due to fisheye scoping. We first analyze the occurrence of mini-loops. We discuss potential solutions and propose a pragmatic and distributed off-line heuristic, which allows each router to compute ldquosaferdquo scope for topology updates. With our method, every mesh router calculates in advance the minimum TTL value that avoids mini-loops at the ldquoscoperdquo boundary - optimal scope that will be set for generating topology update message whenever a neighbor link lost is detected. Simulations show that the proposed algorithm drastically improves safety of Fish Eye OLSR while still retaining its scaling and performance properties.
Conference Paper
Finding a path with enough throughput in multihop wireless ad hoc networks is a critical task of QoS Routing. Previous studies on routing algorithms focused on networks with a single channel rate. The capability of supporting multiple channel rates, which is common in wireless systems, has not been carefully studied in routing algorithms. In this paper, we first carry out a comprehensive study on the impacts of multiple rates, interference and packet loss rate on the maximum end-to-end throughput or path capacity. A linear programming problem is formulated to determine the path capacity of any given path. This problem is also extended to a joint routing and link scheduling optimization problem to find a path with the largest path capacity. We show that interference clique transmission time is inversely proportional to the upper bound of the path capacity, and hence we propose to use it as a new routing metric. Moreover, we evaluate the capability of various routing metrics such as hop count, expected transmission times, end-to-end transmission delay or medium time, link rate, bandwidth distance product, and interference clique transmission time to discover a high throughput path. The results show that different routing metrics lead to paths with significantly different path capacity, and the interference clique transmission time tends to discover paths with higher throughput than other metrics.
Conference Paper
Next generation fixed wireless broadband networks are being increasingly deployed as mesh networks in order to provide and extend access to the internet. These networks are characterized by the use of multiple orthogonal channels and nodes with the ability to simultaneously communicate with many neighbors using multiple radios (interfaces) over orthogonal channels. Networks based on the IEEE 802.11a/b/g and 802.16 standards are examples of these systems. However, due to the limited number of available orthogonal channels, interference is still a factor in such networks. In this paper, we propose a network model that captures the key practical aspects of such systems and characterize the constraints binding their behavior. We provide necessary conditions to verify the feasibility of rate vectors in these networks, and use them to derive upper bounds on the capacity in terms of achievable throughput, using a fast primal-dual algorithm. We then develop two link channel assignment schemes, one static and the other dynamic, in order to derive lower bounds on the achievable throughput. We demonstrate through simulations that the dynamic link channel assignment scheme performs close to optimal on the average, while the static link channel assignment algorithm also performs very well. The methods proposed in this paper can be a valuable tool for network designers in planning network deployment and for optimizing different performance objectives.
Article
In this paper, we propose a new quality link metric, interference and bandwidth adjusted ETX (IBETX) for wireless multi-hop networks. As MAC layer affects the link performance and consequently the route quality, the metric therefore, tackles the issue by achieving twofold MAC-awareness. Firstly, interference is calculated using cross-layered approach by sending probes to MAC layer. Secondly, the nominal bit rate information is provided to all nodes in the same contention domain by considering the bandwidth sharing mechanism of 802.11. Like ETX, our metric also calculates link delivery ratios that directly affect throughput and selects those routes that bypass dense regions in the network. Simulation results by NS-2 show that IBETX gives 19% higher throughput than ETX and 10% higher than Expected Throughput (ETP). Our metric also succeeds to reduce average end-to-end delay up to 16% less than Expected Link Performance (ELP) and 24% less than ETX.
Article
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004. Vita. Includes bibliographical references (leaves 111-118). This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. The expected transmission count (ETX) metric is a new route metric for finding high-throughput paths in multi-hop wireless networks. The ETX of a path is the expected total number of packet transmissions (including retransmissions) required to successfully deliver a packet along that path. For practical networks, paths with the minimum ETX have the highest throughput. The ETX metric incorporates the effects of link loss ratios, asymmetry in the loss ratios between the two directions of each link, and interference among the successive links of a path. Busy networks that use the ETX route metric will also maximize total network throughput. We describe the design and implementation of ETX as a metric for the DSDV and DSR routing protocols, as well as modifications to DSDV and DSR which make them work well with ETX. Measurements taken from a 29-node 802.11b test-bed show that using ETX improves performance significantly over the widely-used minimum hop-count metric. For long paths the throughput increase is often a factor of two or more, suggesting that ETX will become more useful as networks grow larger and paths become longer. We also present a simple model for predicting how packet delivery ratio varies with packet size, and detailed measurements which characterize the test-bed's distribution of link delivery ratios and route throughputs. by Douglas S.J. Couto. Ph.D.
Conference Paper
There has been increased interest recently from military, civil, and commercial sectors in networks capable of self-organization. Routing and channel assignment for multi-hop communications in these networks are complex problems, given the interactions between the various transmissions, all of which must share some fixed bandwidth, and by the lack of a central controller. By enforcing a “reuse distance” similar to the frequency reuse factor in AMPS cellular service, we can route and assign channels to (place) arriving calls in a peer-to-peer network so as to significantly reduce power requirements and interference