Redundant Packets Research Articles

Backpressure Delay Enhancement for Encounter-Based Mobile Networks While Sustaining Throughput Optimality

Backpressure routing, in which packets are preferentially transmitted over links with high queue differentials, offers the promise of throughput-optimal operation for a wide range of communication networks. However, when traffic load is low, backpressure methods suffer from long delays. This is of particular concern in intermittent encounter-based mobile networks which are already delay-limited due to the sparse and highly dynamic network connectivity. While state of the art mechanisms for such networks have proposed the use of redundant transmissions to improve delay, they do not work well when traffic load is high. In this paper we propose backpressure with adaptive redundancy (BWAR), a novel hybrid approach that provides the best of both worlds. This approach is robust, distributed, and does not require any prior knowledge of network load conditions. We also present variants of BWAR that remove redundant packets via a timeout mechanism, and that improve energy use. These algorithms are evaluated by mathematical analysis and by simulations of real traces of taxis in Beijing, China. The simulations confirm that BWAR outperforms traditional backpressure at low load, while outperforming encounter-routing schemes (Spray and Wait and Spray and Focus) at high load.

Double Stairs: A Fault-Tolerant Routing Algorithm for Networks-on-Chip

Reliability is one of the main concerns in the design of networks-on-chip (NoCs) due to the use of deep submicron technologies in fabrication of such products. This paper presents a new fault-tolerant routing algorithm called double stairs for NoCs. Double stairs routing algorithm is a low overhead routing that has the ability to deal with fault. The proposed routing algorithm makes a redundant copy of each packet at the source node and routes the original and redundant packets in a new partially adaptive routing algorithm. The method is evaluated for various packet injection rates and fault rates. Experimental results show that the proposed routing algorithm offers the best trade-off between performance and fault tolerance compared to other routing algorithms, namely flooding, XYX and probabilistic flooding.

Opportunity cooperative embedded platform and control mechanism based on selectivity of time and frequency domain

The opportunistic cooperative platform and adaptive cooperative control scheme were proposed based on the redundancy degree and priority of cooperative data packet, as well as selective characteristics of time domain and frequency domain. First, opportunistic cooperative platform was defined according to the cooperative data stream scale, mapping algorithm, and priority and redundancy of cooperative data packets. Second, under the single or multiple relay network environment and mobility of sensors, the selective characteristics of time and frequency domain were studied. The active domain and negative domain were proposed for adjusting and improving the opportunistic cooperative platform. Third, the opportunistic cooperative control mechanism based on selectivity of time domain and frequency domain (OCC-TFD) was proposed for improving the performance of wireless sensor networks. Finally, the mathematical results demonstrated that the proposed platform and scheme can provide reliable, robust, and efficient data communication services of wireless sensor networks.

An efficient broadcast-based information transfer method based on location data over MANET

In a disaster situation, mobile ad hoc networks can be considered as one of the communication methods when the communication infrastructure is unavailable. Under these circumstances, the number of redundant packets consuming power should be controlled to save battery power and prolong the life of the network. In this paper, we propose an efficient broadcast-based information transfer method using location data to reduce the redundant packets while achieving high data reachability.

3D Real-Time Routing Protocol With Tunable Parameters for Wireless Sensor Networks

A novel 3D real-time geographical routing protocol (3DRTGP) for wireless sensor networks is presented in this paper. 3DRTGP controls the number of forwarding nodes in the network by limiting forwarding to a unique packet forwarding region (PFR). PFR selection is based on the network density around each of the forwarding nodes, which reduces the number of redundant packet transmissions, collisions, and congestion. This enables 3DRTGP to meet the real-time requirements of a time sensitive application. In order to meet the packet delivery delay deadline, a forwarding node uses its own delay parameters, such as queuing and processing delays, and the expected number of hops to the destination to make a forwarding decision. 3DRTGP does not require an explicit exchange of neighboring information, such as location information. 3DRTGP is evaluated through extensive simulations under various network densities and traffic load conditions, which provides network tuning parameters to meet the real-time requirements of applications. 3DRTGP heuristically solves the void node problem (VNP) in 3-D deployments. It is demonstrated that 3DRTGP resolves VNP given that there is no network partitioning. 3DRTGP significantly outperforms similar 3-D geographical routing protocols in terms of end-to-end delay and miss ratio.

MIMO V-BLAST Scheme Based on Physical-Layer Network Coding for Data Reliability in Emerging Wireless Networks

The multiuser multiple input multiple output (MU-MIMO) proficiency is practicable to significantly improve the diversity and multiplexing gain in emerging wireless networks. Physical-layer network coding (PNC) can efficiently manage and improve the utilization of available spectrum. To resolve the data reliability and diversity gain, a kind of combination called Vertical-Bell Laboratories Layered Space-Time (V-BLAST) and PNC has brought forth a V-BLAST with PNC (V-BLAST-PNC) strategy to enhance the throughput and the performance of emerging wireless networks. We propose a novel cross-layer V-BLAST-based PNC scheme to avail the diversity in multiplexing gain by packet redundancy. The redundancy is introduced to improve the throughput and energy efficiency performance in MU-MIMO by avoiding the packets retransmissions at an upper layer. Experimental evaluation is based on BPSK/QPSK modulation over flat fading channels with the zero forcing and minimum mean square error equalizers. Based on simulation results, we conclude that the proposed V-BLAST-PNC scheme has fewer packets retransmissions and better throughput when compared with the state-of-the-art traditional solutions.

Accomplishing Consummate Throughput with Delay and Power Control in MANET

Mobile Ad Hoc Network is a self-configuring, autonomous, infrastructure less network of movable nodes which will be automatically connected by wireless connection with no access point. The nodes are free to move anywhere in the set of connections and the topology of MANET remains unpredictable. The major complexity with the available two hop relay protocols in MANET environment is to achieve the optimized throughput with reduced packet delivery delay. A generalized collection based two-hop relay and redundancy of the packet is used to attain the reduced delay. The complex process of packet delivery in MANET utilizes Routine Response Control and Modified Markov chain model. Tuning carefully the parameters, the transmission range, the packet redundancy and the group size help to achieve the optimized throughput with the reduced packet delivery delay. Transmission power of a node is controlled which helps in achieving the optimized throughput and reduced delay.

A Novel Broadcast Scheme DSR-based Mobile Adhoc Networks

Traffic classification seeks to assign packet flows to an appropriate quality of service (QoS). Despite many studies that have placed a lot of emphasis on broadcast communication, broadcasting in MANETs is still a problematic issue. Due to the absence of the fixed infrastructure in MANETs, broadcast is an essential operation for all network nodes. Although the blind flooding is the simplest broadcasting technique, it is inefficient and lacks resource utilization efficiency. One of the proposed schemes to mitigate the blind flooding deficiency is the counter based broadcast scheme that depends on the number of received duplicate packets between the node and its neighbors, where the node compares the duplicate packet itself and each neighbor node that previously re-broadcasted a packet. Due to the fact that existing counter-based schemes are mainly based on the fixed counter based approach, these schemes are not efficient in different operating conditions. Thus, unlike existing studies, this paper proposes a dynamic counter based threshold value and examines its effectiveness under the Dynamic Source Routing Protocol (DSR) which is one of the well-known on-demand routing protocols. Specifically, we develop in this paper a new counter based broadcast algorithm under the umbrella of the DSR, namely, Inspired Counter Based Broadcasting (DSR-ICB). Using various simulation experiments, DSR-ICB has shown good performance especially in terms of delay and the number of redundant packets.

Adaptive Coding Optimization in Wireless Networks: Design and Implementation Aspects

A fundamental challenge in wireless networks is how to handle packet loss due to noise, interference, and dynamic channel effects, especially when there is no per-packet acknowledgement due to additional delay and potential loss of feedback packets. We design and implement a packet coding optimization scheme, applied at the source node, to enhance end-to-end transmission reliability in a lossy multi-hop network. Specifically, each source node transmits a file of packets to its destination node in the network where the end-to-end packet acknowledgement is not readily available because of the possible error or delay effects over multiple hops. By simply retransmitting packets, a source node cannot guarantee innovative packet arrivals at the destination node. Thus, we design an optimization scheme for adaptive packet coding applied at the source node to avoid transmitting redundant packets, thereby significantly improving the throughput, even for the case of a single unicast session. This scheme does not require any knowledge of network topology and can seamlessly operate with any routing or network coding protocol used at the intermediate relay nodes. We analyze the throughput properties of coded transmissions and verify the feasibility of performance gains via simulations. Then, we provide high fidelity emulation testbed results with real radio transmissions over emulated channels to evaluate the throughput gains. Without relying on end-to-end acknowledgment for each packet, we show that the adaptive packet coding optimization scheme can achieve significantly higher throughput than the retransmission scheme in lossy networks with unicast traffic.

English

Video transmission over the wireless network faces many challenges. The most critical challenge is related to packet loss. To overcome the problem of packet loss, Forward Error Correction is used by adding extra packets known as redundant packet or parity packet. Currently, FEC mechanisms have been adopted together with Automatic Repeat request (ARQ) mechanism to overcome packet losses and avoid network congestion in various wireless network conditions. In the current Adaptive FEC mechanism, the FEC packets are decided by the average queue length and average packet retransmission times. The Adaptive FEC mechanisms have been proposed to suit the network condition by generating FEC packets adaptively in the wireless network. However, the current Adaptive FEC mechanism has some major drawbacks such as the reduction of recovery performance which injects too many excessive FEC packets into the network. This is not flexible enough to adapt with varying wireless network condition. Therefore, the enhancement of Adaptive FEC mechanism (AFEC) known as Enhanced Adaptive FEC (Enface) has been proposed. The aim is to improve recovery performance on the current Adaptive FEC mechanism by injecting FEC packets dynamically based on varying wireless network conditions. Based on the findings, the optimal amount of FEC generated by Enface mechanism can recover high packet loss and produce good video quality An Enhanced Random Early Detection Forward Error Correction (ERED-FEC) mechanism is implemented to improve the quality of video transmissions over Wireless Local Area Networks (WLANs).

An Efficient Data Aggregation Method for Event-Driven WSNs: A Modeling and Evaluation Approach

This paper proposes and models an efficient data aggregation method for wireless sensor networks (WSNs). In the proposed data aggregation method, every cluster head (CH) node incorporates a local forwarding history to decide whether to forward or to drop a recently received packet. When a new packet arrives at a CH node, a threshold value is calculated based on the information of the forwarding history; then, a random number is generated and compared with the threshold value to determine whether the packet should be dropped or not. In fact, the CH node forwards the new packet with the probability of 1 ? p and drops it with probability of p where the parameter p is determined based on the forwarding history. In order to evaluate the proposed data aggregation method, two approaches consisting of simulation and analytical modeling are used. Various scenarios are considered in simulations conducted with NS2 software to compare the proposed data aggregation method with four previously proposed methods. Results reveal that the proposed method (1) aggregates more than 70 % of redundant packets, (2) reduces the network end-to-end delay by at least 22 %, and (3) reduces the missed event rate compared with the other methods. The proposed method is also evaluated by means of an analytical model based on queuing networks. The model accurately estimates the network performance utilizing the proposed data aggregation method. Comparisons of the results obtained by the proposed model and simulations confirm that the proposed model has at most 7 % prediction error. The proposed model allows WSN designers to easily achieve useful information about their networks before the establishment and manufacturing of the networks.

An efficient and reliable geographic routing protocol based on partial network coding for underwater sensor networks.

Efficient routing protocols for data packet delivery are crucial to underwater sensor networks (UWSNs). However, communication in UWSNs is a challenging task because of the characteristics of the acoustic channel. Network coding is a promising technique for efficient data packet delivery thanks to the broadcast nature of acoustic channels and the relatively high computation capabilities of the sensor nodes. In this work, we present GPNC, a novel geographic routing protocol for UWSNs that incorporates partial network coding to encode data packets and uses sensor nodes’ location information to greedily forward data packets to sink nodes. GPNC can effectively reduce network delays and retransmissions of redundant packets causing additional network energy consumption. Simulation results show that GPNC can significantly improve network throughput and packet delivery ratio, while reducing energy consumption and network latency when compared with other routing protocols.

Lightweight, latency‐aware routing for data compression in wireless sensor networks with heterogeneous traffics

AbstractIn many applications and scenarios, sensors have to regularly report what they monitor from the environment and quickly notify the sink node of event occurrence in the sensing field. An in‐network data reduction technique, such as data aggregation and data compression, can help diminish the amount of data sent from sensors, which not only saves the network bandwidth but also preserves sensors' energy. However, such technique does not consider packet latency because of the aggregation or compression operation. When some sensors generate regular reports in lower data rates, their packets have to spend longer time to be aggregated or compressed, resulting in higher packet delays. Besides, when events occur, the network could suffer from instant congestion due to the generation of numerous event notifications. Motivated with the aforementioned observations, the paper develops a lightweight, latency‐aware routing for data compression (L2DC) scheme to reduce packet latency when applying the compression technique, to reduce the amount of data generated from sensors. L2DC gives event notifications a higher priority over regular reports and eliminates unnecessary notifications to avoid bursty network congestion. In addition, L2DC facilitates the data compression process by allowing each sensor to determine whether to keep packets for compression locally or to send them to a neighbor to be compressed in a distributed manner. Our L2DC scheme can be easily built on most ad hoc and sensor routing protocols because it provides auxiliary redundant packet elimination and relay node selection mechanisms to reduce packet latency. By using the ad hoc on‐demand distance vector protocol as the example, simulation results demonstrate the effectiveness of the L2DC scheme. Copyright © 2015 John Wiley & Sons, Ltd.

Source-Aware Redundant Packet Forwarding Scheme for Emergency Information Delivery in Chain-Typed Multihop Wireless Sensor Networks

For emergency information delivery of chain-typed multihop wireless sensor networks in closed long tunnel (CWSN-C), the scheme of sending the same packet multiple times is a good choice. In this paper, taking the application of rigid sliding guide obliquity monitoring in deep shaft as background, the source-aware redundant packet forwarding scheme for emergency information delivery in CWSN-C (SRPFEC) is proposed firstly. Secondly, more of comprehensive factors including application QoS and energy efficiency are considered for determining the number of redundant packets. Then, a method of solving for the number of redundant packets is proposed. Finally, Monte Carlo method and network simulation are employed to study the performances of proposed SRPFEC. The results show that (1) non-ACK scheme is highly suitable for the condition of large network size and hazardous wireless communication environment; (2) the non-source-aware solution is easy to use and is suitable for the occasion where the node could be replaced on demand expediently; (3) the source-aware solution has the better performance in energy efficiency and is suitable for the occasion where the network lifetime needs to be determined before deployment, and the node could not be replaced easily.

A reliable data transfer protocol based on twin paths and network coding for underwater acoustic sensor network

MPNC (multiple path and network coding) is proposed as a reliable transport protocol for UWASN (underwater acoustic sensor network). In MPNC, after three disjoint paths being established, two groups of packets (A and B), coded by network coding, are transmitted over the two side paths respectively, and another group of packets C = A ⊕ B are transmitted over the middle path. That is, any two paths can work together as a redundant path for another path, and the reliable transmission of one packet can be guaranteed by 1.5 packets. In order to reduce the number of redundant packets without affecting the transmission reliability, the packets of group C are coded further at special ratio by network coding as shareable redundant packets according to the link error, and a reliable transport protocol TPNC (twin path and network coding) based on two paths and network coding is proposed in this paper. In TPNC, after two disjoint paths, called twin paths, being established, two groups of packets (A and B), coded by network coding, are transmitted with their own shareable redundant packets over the two paths respectively to guarantee the data packet transmission reliability. The results of simulations show that, compared with MPNC, TPNC can acquire similar data delivery ratio with lower energy consumption.

Issues of Data Aggregation Methods in Wireless Sensor Network: A Survey

In Wireless Sensor Networks (WSN) sensor nodes are deployed in a region to sense the information. These sensor nodes sense the similar information and sends it to sink node. This thing leads to redundancy at sink node. Sink node wastes most of its energy in processing redundant packets. To save the energy of node in order to prolong the network lifetime there is need to eliminate redundancy. Data aggregation is a process in which intermediate node receives multiple input packets performs aggregation and produce single output packet in the network. This process will reduce the number of redundant packets in the network. But redundancy sustains reliability. Therefore there is need to maintain redundancy but it should be up to an adequate level. In this paper we have focused on different issues in data aggregation process such as delay, redundancy elimination, accuracy and traffic load and mentioned various methods to solve those issues and then we compared some data aggregation techniques based on strategy, delay, redundancy, average energy consumption and traffic load. Further we have proposed a model based on our study which performs data aggregation at multiple levels and not only maintains the tradeoff between energy conservation and reliability but also addresses all the issues in data aggregation technique.

Bit-Express: A Loss Tolerant Network Transmission via Network Coding

Lossy communication networks may be one of the most challenging issues for Transmission Control Protocol (TCP), as random loss could be erroneously interpreted into congestion due to the original mechanism of TCP. Network coding (NC) promises significant improvement in such environment thanks to its ability to mix data across time and flows. Therefore, it has been proposed to combine with TCP called TCP-NC by MIT. In this paper, we dedicated to quantifying the R, a key parameter for redundant packets, and make it close to the loss rate as much as possible, which has not been considered in the previous research. All of these are done by the sender who is completely unconscious of the network situation. Simulation results by NS2 under both wired and wireless networks showed that our method retains all the advantages of TCP-NC, and meanwhile outperforms TCP-NC and the other TCP variants in time-varying lossy networks.

Energy Efficient with Network Coding Multipath Routing Algorithm in Wireless Sensor Networks

Network coding is a new paradigm in data transport and promises to change many aspects of wireless sensor network (WSN). Thanks to the recently developed network coding techniques, a high-throughput low-complexity hierarchical protocol can be facilitated due to the multiple-source relay-based data transmissions built on the network coding schemes, especially for the data communications between the source node and destination node. In this paper, we propose an Energy efficient that carefully couples Network coding and Multipath routing algorithm in Wireless Sensor Networks (ENM-WSN). Through an analytical study, we provide guidance on how to choose parameters in our scheme and demonstrate that the scheme is efficient in both multipath and energy consumption. We also present an algorithm for deciding the network coding scheme for a node to further reduce energy consumption by minimizing redundant packet transmissions. Simulation results show that, with the proposed energy efficient with network coding in WSN multipath routing protocol (ENM-WSN), energy consumption, packet delivery ratio, and network lifetime can be improved in most of cases. It is an available approach to multipath routing decision.

A restricted flooding mechanism for efficient anycast server localization in MANETs

In wireless networks, reducing the number of redundant packets is one of the important mechanisms to minimize the required network bandwidth and the power consumed by network nodes. In this paper, an efficient and stateless flooding mechanism for anycast routing in wireless mobile ad hoc networks is proposed. The mechanism uses the technique of expanding ring search to decrease the related message traffic. A model of this mechanism is described. Based on this model, an extensive simulation study, together with real field experiments, has been conducted to investigate the performance of the proposed mechanism for anycast server localization. The simulation model has been developed in terms of a class of extended Petri nets that provide the possibility to conveniently represent parallelism of events and processes in the network. In simulation and real work experiments, fundamental performance metrics--response ratio, relative traffic and average response time--were investigated with varying distance of transmission and different combinations of model parameters. The obtained results show that the proposed approach to server localization in mobile ad hoc networks has good characteristics. As was demonstrated with a prototype system, the proposed routing method can be easily implemented at the application layer, without any changes at lower layers of the network protocol stack.

Delay and Capacity Analysis in MANETs with Correlated Mobility and <formula formulatype="inline"><tex Notation="TeX">${f}$</tex> <mathgraphic graphicformat="GIF" fileref="guo-ieq1-2298014.gif"/></formula>-Cast Relay

Many studies have presented the order sense results of information transmission capacity and packet delivery delay in mobile ad hoc networks (MANETs). To achieve the fundamental understanding of MANETs, we focus on deriving the closed-form expressions of the network capacity and end-to-end delay. A MANET with the generalized correlated mobility model is considered in this paper, where the mobility of nodes clustered in one group is confined within a specified area, and multiple groups move uniformly across the network. We also leverage limited packet redundancy to speed up the packet transmission, i.e., each source node is allowed to distribute at most $f$ copies of each packet in its delivery process. Specifically, we first propose an effective multi-hop scheduling-routing scheme under the correlated mobility model, and then develop the closed-form expressions of both per node throughput capacity and expected end-to-end delay. We further explore the tradeoff between throughput capacity and packet delay by using packet redundancy $f$ . The simulation studies validate our theoretical results.