Acknowledgement Packets Research Articles

EDCS: Efficient data collection systems by using bundling technology for effective communications

The energy of Wireless Sensor Network (WSN) in edge network is limited. In order to save energy, data bundling is proposed to reduce the energy consumed in setting up connection links by joining several packets into a single unit. However, although current data bundling schemes can reduce energy consumption, they will increase the delay of data routing, so it makes the multi-hop end to end delay a lot in WSN. Also, there is no appropriate solution to tackle the delayed growing problem caused by data bundling. And the energy consumption of the Acknowledgment (ACK) transmission is not comprehensively considered either. Regarding to those issues of previous researches, in this paper, a Data and ACK Bundling Scheme (DAB) is proposed to aggregate several data or ACK packets into a single unit to reduce the energy consumption as well as the end to end delay of the WSN. In the proposed DAB scheme, not only multiple packets but also ACK bundling into a single unit can reduce energy consumption. More importantly, the parameters of bundling technology are optimized from a global perspective in DAB scheme, so that WSN can not only improve the network lifetime, but also reduce the end to end delay which is impossible in previous studies. The theoretical analysis and experimental results illustrate that, while ensuring the reliability of data collection, our DAB scheme improves the energy efficiency by 29.03 % and reduces the delay by 22.29 % when compared with our traditional data collection scheme.

Self-Tuning of Signal Detection Level for Energy Detection-Based Carrier Sense in Low-Power Wide-Area Networks.

Carrier sense allows end devices to improve the communication quality through autonomous decentralization by consuming power. In particular, energy detection-based carrier sense can improve communication quality compared with peak detection-based carrier sense. To improve the trade-off between communication quality and energy consumption in low-power wide-area networks (LPWANs), this study proposes a self-tuning method for the signal detection level of an energy detection-based carrier sense, that is, the carrier sense level in sub-GHz band LPWANs. In the proposed method, the carrier sense level of each end device is determined based on the reception success probability of the acknowledgment packet, such that they become low carrier sense levels for an end device with low probability and high carrier sense levels for an end device with high probability. The proposed method enables autonomous decentralized derivation of the carrier sense level using only existing protocols. Numerical examples show that the proposed method can improve the performance of end devices with a high path loss to a gateway.

Efficient LQG control for wireless networked control systems without packet acknowledgement

This paper studies the linear quadratic Gaussian (LQG) control problem for wireless networked control systems (WNCSs) without packet acknowledgement. In WNCSs, packets may be randomly lost in both control and observation channels, and non-acknowledgement (non-ACK) mechanisms (e.g. UDP-like protocols) are generally adopted to achieve real-time control and reduce energy consumption. For general non-ACK systems, it is well known that the optimal controller is not yet available, and the performance of existing suboptimal controllers is poor because they either adopt a fixed control law or rely on a poorly performing filter. By using a moment-preserving Gaussian approximation approach, an efficient filter is proposed to approximately estimate system states. Based on the approximate state estimates of the proposed filter, an approximate optimal controller with a time-varying control gain for WNCSs is further designed by using a dynamic programming approach. The proposed controller has excellent performance and becomes the optimal controller under special system parameters. Numerical simulations show the correctness and effectiveness of the obtained results.

Delayed Response and Random Backoff First for Low-Power Random Access of IoT Devices with Poor Channel Conditions

As IoT services become more active, the density of IoT devices is increasing, and massive connectivity technology is needed to support numerous devices simultaneously. In addition, IoT devices are often battery-powered, and during random access, it is necessary to reduce the power consumption to extend the lifetime of the devices. In particular, devices with poor channels need to send at a very low transmission rate through a large number of repetitions, and longer packet lengths can increase the probability of collisions, increasing the power consumption while shortening the lifetime of the IoT system. Dividing devices into groups based on the number of repetitions and allocating different resources to each group can reduce collisions for bad-channel devices, but it can be difficult to support large connections, due to the inefficient use of resources. This paper proposes schemes to reduce the collision probability of bad-channel devices while allowing IoT devices to use shared resources, instead of dividing resources by groups. There are two versions of the proposed schemes. The first method reduces collisions by delaying the response of a bad-channel device, and in the meantime, eliminating interference from other devices, assuming that the bad-channel device is not sensitive to delay. Instead of checking the response, and then, performing a random backoff when no acknowledgement packet is received, the second proposed method reverses the order of response checking and random backoff, that is, it first performs a random backoff, and then, checks the response to decide whether to retransmit. The proposed method can increase the lifetime of the IoT system by reducing the collision probability of a bad-channel device, without degrading the performance of other devices.

Network Topology Inference Based on Timing Meta-Data

A set of low-cost sensors is deployed to infer the network topology of a self-organizing wireless network. The sensors operate in a non-invasive fashion, extracting only the timings of data packets and acknowledgment (ACK) packets from all nodes in a network. The meta-data also reports the source node of each packet, but not the destination nodes or the contents of the packets. A central processor collects the meta-data from the sensors, and the goal is for the processor to infer the network topology based solely on such information. Prior work leveraged causality metrics to identify which links are active. If the data timings and ACK timings of two nodes – say node 1 and node 2, respectively – are causally related, this may be taken as evidence that node 1 is communicating to node 2 (which sends back ACK packets to node 1). This paper starts with the observation that packet losses can weaken the causality relationship between data and ACK timing streams. To obviate this problem, a new Expectation Maximization (EM)-based algorithm is introduced – EM-causality discovery algorithm (EM-CDA) – which treats packet losses as latent variables. EM-CDA iterates between the estimation of packet losses and the evaluation of causality metrics. The method is validated through extensive experiments in wireless sensor networks on the NS-3 simulation platform.

Improving the TCP Newreno Congestion Avoidance Algorithm on 5G Networks

Enhancing Transmission Control Protocol (TCP) performance is one of the key solutions for improving the performance of modern wireless communication networks. It is a highly dependable protocol for communication between network hosts based on an internet protocol (IP). It uses packet sequence numbering and acknowledgment (ACK) packets to ensure that data is recoverable in the event of problems like data loss, and corruption. Loss-based Congestion Control (CC) algorithms overreact and underperform in the presence of rapid channel oscillations, resulting in buffer bloat and significant delays. The goal of this paper is to develop an efficient congestion control mechanism for the new TCP agent Newreno over the fifth generation (5G) network, as well as to improve the increment and decrement strategy for adjusting the congestion window (cwnd) during the congestion avoidance phase, It also fast adapts to the current network requirements and adjusts the transmission rate accordingly. TCP enhancements can improve performance under dynamic traffic loads and over long product channels with high bandwidth. As a result, when such a TCP congestion control mechanism is improved, the network’s throughput increases, and low packet losses, and delay are reduced.

Adaptive Congestion Control Mechanism to Enhance TCP Performance in Cooperative IoV

One of the main causes of energy consumption in Internet of Vehicles (IoV) networks is an ill-designed network congestion control protocol, which results in numerous packet drops, lower throughput, and increased packet retransmissions. In IoV network, the objective to increase network throughput can be achieved by minimizing packets re- transmission and optimizing bandwidth utilization. It has been observed that the congestion control mechanism (i.e., the congestion window) can plays a vital role in mitigating the aforementioned challenges. Thus, this paper present a cross-layer technique to controlling congestion in an IoV network based on throughput and buffer use. In the proposed approach, the receiver appends two bits in the acknowledgment (ACK) packet that describes the status of the buffer space and link utilization. The sender then uses this information to monitor congestion and limit the transmission of packets from the sender. The proposed model has been experimented extensively and the results demonstrate a significantly higher network performance percentage in terms of buffer utilization, link utilization, throughput, and packet loss.

A Duty Cycle-Based Gateway Selection Algorithm for LoRaWAN Downlink Communication

Long Range Wide Area Network (LoRaWAN) has been developed to meet the requirements for the enormous device-to-device communication of Internet of Things (IoT) networks, which consist of a large number of participating devices spread over large coverage areas with low data rates and low power consumption. It supports communications in both directions, uplink, and downlink directions. However, the downlink communication in the current LoRaWAN raises the bottleneck issue at gateways due to the used gateway selection algorithm. This paper proposes a novel gateway selection algorithm based on the duty cycle time-off values for the existing gateways, Duty Cycle Gateway Selection (DCGS), to direct acknowledgment packets as downlink traffic towards the most suitable gateway. Thus, the proposed system avoids subsequent retransmission of previously sent traffic that leads to excessive traffic overloading the network. The proposed system avoids exhausting a gateway duty cycle with downlink traffic by distributing the downlink traffic among available gateways based on the duty cycle time off. DCGS is evaluated using FloRa and INET frameworks in the well-known network simulator OMNeT++. The result shows the superior performance of the proposed approach over the existing Signal-to-Noise ratio (SNR) based selection mechanism. It clearly indicates that the DCGS maintains a better confirmed packet delivery rate while reducing number of retransmissions, collisions, and power consumption.

A Robust, Scalable, and Energy-Efficient Routing Strategy for UWSN Using a Novel Vector-Based Forwarding Routing Protocol

The Underwater Wireless Sensor Network (UWSN) is capable of supporting a wide range of low-data-rate acoustic sensor networks, as well as scalability and energy-efficient routing algorithms. Furthermore, because of the lower bandwidth and longer propagation delays, energy consumption is a major concern with underwater networks. Because radio transmissions are unstable in deep water, a UWSN often communicates via acoustic channels. UWSN features create constraints on data packet transmission and energy-efficient routing. The hardest challenge is creating an effective routing protocol for UWSNs that uses sensor node localization. There have been several routing algorithms reported for identifying nodes via a localization process. This paper proposes a novel vector-based forwarding (NVBF) and efficient depth-based routing (DBR) protocol to provide robust, scalable, and energy-efficient routing. Efficient DBR is a stochastic model that can survive even in acoustic channels with substantial transmission loss. An adjacent node table is created to decrease the energy consumption and end-to-end delay by limiting the adjacent node request generated every single time. The redundant packet transmission is reduced by creating a packet queue which also minimizes the energy. The NVBF algorithm uses a random waiting time to overcome the collision that occurs while sending the acknowledgment packets. Based on the previous sender’s depth and the depth of the own node, the DBR makes packet transmission decisions. The experiments are conducted using the NS3 simulator and the efficiency of the proposed approach is evaluated in terms of propagation delay, network lifetime, energy consumption, and delivery ratio. When compared to the existing techniques such as DBR, VBF, and energy-efficient DBR (EDBR), the proposed methodology offers improvement up to 40% and 30% in terms of propagation delay and delivery ratio.

The impact of finite data and energy storages in performance of relay networks with energy harvesting

We consider a wireless network consisting of a source, an energy harvesting relay and a destination. A discrete time schedule is assumed. In the first stage, the energy packets and the data packets are sent to the relay node and stored in the finite battery and data storages, respectively. In the second stage, the stored data is sent towards the destination. It is supposed that at each time slot, only a packet of energy or data could be transmitted. The probability of successful transmission is derived for both data and energy packets. An acknowledgment packet reports the status of the buffers to the source node, based on the probability of successful transmissions. The network Packet Delivery Ratio (PDR) is considered to evaluate the performance of the system. Thus, a maximization problem is defined over discrete parameters of the network on data and energy buffer constraints. The optimization problem turns out to be non-convex, thus, it is converted to the subproblems which are solved individually. The closed form expressions are derived to determine the number of the packets during each time frame. The analytical results are verified by the simulations and show the effect of energy and data capacity on PDR.

Partial Diffusion Markov Model of Heterogeneous TCP Link: Optimization with Incomplete Information

The paper presents a new mathematical model of TCP (Transmission Control Protocol) link functioning in a heterogeneous (wired/wireless) channel. It represents a controllable, partially observable stochastic dynamic system. The system state describes the status of the modeled TCP link and expresses it via an unobservable controllable MJP (Markov jump process) with finite-state space. Observations are formed by low-frequency counting processes of packet losses and timeouts and a high-frequency compound Poisson process of packet acknowledgments. The information transmission through the TCP-equipped channel is considered a stochastic control problem with incomplete information. The main idea to solve it is to impose the separation principle on the problem. The paper proposes a mathematical framework and algorithmic support to implement the solution. It includes a solution to the stochastic control problem with complete information, a diffusion approximation of the high-frequency observations, a solution to the MJP state filtering problem given the observations with multiplicative noises, and a numerical scheme of the filtering algorithm. The paper also contains the results of a comparative study of the proposed state-based congestion control algorithm with the contemporary TCP versions: Illinois, CUBIC, Compound, and BBR (Bottleneck Bandwidth and RTT).

Dolphin swarm optimization algorithm for software‐defined antenna selection algorithm in underwater acoustic sensor network

SummaryUnderwater acoustic sensor network (UASN) employs to monitor the aquatic environment. The underwater nodes deploy for continuous and real‐time monitoring. The underwater nodes deploy at different depths to facilitate data forwarding from ocean floor sensor to buoys node. However, the underwater network has limited network resources such as the battery, bandwidth, and susceptibility to mobility, thermographic conditions, and propagation delay. The propagation delay and thermographic condition prolong node packet processing and delay network operation. The delayed network operation increases node battery consumption and overhead. Hence, a bio‐inspired dolphin swarm optimization algorithm (DSA) implements to select the optimal antenna for data transmission. The DSA selects the optimal antenna for data communication by evaluating the acknowledgment packet obtained for data transmitted through multiband antennas. The DSA was simulated in an NS2‐Aquasim environment and testbed to evaluate its performance. The DSA improved data reliability, packet delivery ratio by 97%, and reduced bit error rate (BER), end‐to‐end delay compared to traditional algorithms.

Integral sliding-mode robust observer-based congestion control for wireless access networks

Designing a robust active queue management (RAQM) is mandatory to avoid congestion in networks with wireless access links, because transmission control protocol (TCP) can detect congestion after its occurrence in a communication network and wireless links suffer from bottleneck capacity variations caused by fading and packet error rate (PER) in the acknowledgement packets. Furthermore, the average window size cannot be measured explicitly from the output signal and input and state delay are imposed to a network, which complicate the RAQM design problem in nonlinear models. So, the main contribution of this study is to design a robust observer based control procedure based on integral sliding mode protocol to estimate the average window size, to control congestion in a TCP/RAQM network and to compensate input and state delay. Simulation results via professional simulator NS-2 and SIMULINK confirm that the procedure can effectively estimate the window size and can robustly avoid congestion.

Slot Reallocation and Rejection for Collision Avoidance in Autonomous TSCH Networks

The IEEE 802.15.4-2015 TSCH (Time Slotted Channel Hopping) standard provides high-reliability, deterministic delay, and energy efficiency with the channel hopping and the TDMA. The standard does not specify the scheduling method, which is an essential part of the solution. One of the representative studies in TSCH scheduling is Orchestra. It is an autonomous scheduling method with minimal overhead that does not require a negotiation process between nodes. However, with high traffic load, performance of the Orchestra is greatly degraded because of its fixed schedule. If a node has children, continuous collisions occur in the slot of the node. We propose a novel algorithm called SRCA (Slot Reallocation for Collision Avoidance), as a solution for this problem. The SRCA autonomously updates the schedule. When a child requests a slot reallocation, the parent allocates a new slot with a low probability of collision. Another algorithm called SJCA (Slot reJection for Collision Avoidance) is further proposed in this work. It improves the SRCA to operate in an environment with interference where a sending node can disturb a transmission from a hidden node. In the SJCA, a node determines whether a collision due to interference will occur in the slot newly allocated by the parent. If so, it rejects the slot and requests again. We compare the performance of the SRCA and the SJCA against the Orchestra and e-TSCH-Orch through simulations. It is confirmed that the SJCA is robust to interference. In most cases, the SJCA shows better performance of PAR (Packet Acknowledgement Ratio), PLR (Packet Loss Rate), and latency than others. It is also verified that the SJCA provides high-reliability and low latency compared to existing technologies.

Acknowledgment scheme using cloud for node networks with energy-aware hybrid scheduling strategy

Cloud computing is attracting a lot of traffic on the Internet. Due to the distributed nature of the ad hoc networks, there is no clear path for the communication between nodes. Additionally, there is no centralized or master node to guide the rest of the nodes in the distributed networks. Since the networks are continually expanding, it is vital to mention that there is a substantial increase in the number of attacks. As such, we became interested to consider monitoring the wireless network using cloud. This way, we will be able to deal with varies attacks and to provide better guidance for the networks. In this paper, we propose a new approach for acknowledgement scheme, using a one hop cloud technology, called Cloud Acknowledgement Scheme. This approach strengthens the wireless network by introducing cloud as a monitoring tool as well as to act as a leader node. An efficient cloud provisioning needs a better scheduling scheme. Towards this end, this paper is proposing a new approach to support the short-lived nature of acknowledgment packets in an efficient manner. Our proposed approach constitutes of two developed algorithms that act as one. These scheduling algorithms help to accomplish the purpose of cloud acknowledgment scheme. It is also important and significant to consider the cloud’s awareness of energy consumption to reduce the impact on the environment. Towards this end, monitoring energy consumption is achieved by assigning priorities on the given tasks and balancing the performance and the energy of the cloud. The proposed approach is demonstrated and proved as working models using simulations. The results suggest that our proposed approach has the potential to alternate other existing acknowledgement schemes.

Adaptive Redundancy-Based Transmission for Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are built upon tens to thousands of sensor nodes dispersed across a geographical area. Most sensor nodes have limited on-board resources, such as limited computing capabilities and limited power. These issues can reduce the reliability of the sensor nodes, which, in turn, affects the robustness of the WSN as a whole. One of the components that can be affected is the data transmission system of the sensor nodes. We propose a reliable transport layer protocol that uses a combination of redundant packets and probabilistic transmission to ensure reliable transmission of data while maintaining the efficiency of the network. The proposed protocol does not require acknowledgement packets, such as the transmission control protocol (TCP) and yet its efficiency is similar to that of the user datagram protocol (UDP). In this paper, we explain the proposed protocol and demonstrate how it can achieve 7% improvements in reliability while maintaining 77% efficiency compared to UDP.

On LQG control design for network systems with/without acknowledgments using a particle filtering technology

This paper focuses on the behavior of a linear quadratic Gaussian (LQG) controller for discrete-time systems utilizing industrial communication protocols. A new design of LQG problem is investigated for constrained networked control systems by using a new class of a quadratic cost function with a communication cost. This paper is considered two industrial communication protocols namely: the transportation control protocol (TCP), in which the sender should receive an acknowledgment regarding the delivery of the sending packets and the user datagram protocol (UDP) where the acknowledgment signal is absence. In the latter one, the driver (actuation) does not afford acknowledgment to inform the controller/estimator regarding the reception of the action packets. In such setting, the UDP-like protocol can react nonlinearly, where the absence of the acknowledgment creates a nonlinear optimization control law. In this sense, a LQG with standard Kalman filtering is failed because the separation principle can not reached. Under this setting, a suboptimal methodology can be successfully implemented to compensate the absence of communication and acknowledgment packets. The prescribed performance of networked system is sustained in the presence of communication constraints. The probabilities of the data signal dropouts are expressed in terms of random Bernoulli processes. Then, simulation results are provided to demonstrate the validity of the proposed schemes and to compare them with others from literature.

Performance Analysis of MultiACK-SFAMA for Underwater Acoustic Networks

MultiACK-Slotted Floor Acquisition Multiple Access (MultiACK-SFAMA) is a medium access control (MAC) protocol that has been proposed for underwater acoustic networks to overcome the problems of repeating the entire Request To Send (RTS) and Clear To Send (CTS) contention and DATA transmission cycle. In Slotted Floor Acquisition Multiple Access (S-FAMA), when an acknowledgement (ACK) fails to reach the transmitter, the entire cycle repeats. Multi-ACK mechanism has been analyzed in Shahabudeen et al. (IEEE J Ocean Eng 39(1):74–89, 2014). We chose to incorporate this mechanism in S-FAMA to enhance its performance. MultiACK-SFAMA is a modified version of S-FAMA and is aimed to avoid that a successful data transmission is wasted because the acknowledgement is lost, thus saving energy, by using a train of ACKs instead of a single ACK for each DATA packet. By using MultiACK, the probability that an ACK would be received successfully increases. In underwater acoustic networks, due to high propagation delay the cost of losing an ACK is very high and significantly impacts the performance of the protocol. The MultiACK mechanism has been proposed and analyzed to improve the S-FAMA performance. The MultiACK mechanism increases the probability of receiving at least one ACK packet by replying with a train of ACK packets. In this paper we present a mathematical analysis of MultiACK-SFAMA. The paper presents analysis of the performance of MultiACK-SFAMA as a function of transmission range, number of nodes and bit error rates. The results show that the throughput improvement (%) achieved is improved by using a MultiACK train instead of a single ACK. The MultiACK train improves the probability of receiving an ACK by 65.05%, for a BER of 0.005 and saves energy.

RFL: Robust fault localization on unreliable communication channels

The current Internet is vulnerable to various attacks, e.g., source spoofing and flow hijacking attacks, which are incurred by misconfigurations or attacks. Either users or network operators are unable to easily localize these faults. Existing fault localization mechanisms can detect such attacks under an assumption that localization is performed upon reliable communication channels. Unfortunately, the assumption does not always hold. The forwarding paths of localization are not always reliable. Packets are usually dropped for some reasons. In particular, adversaries can interfere with fault localization by maliciously dropping packets. In this paper, we relax the assumption and propose a robust data-plane fault localization protocol named RFL that can localize faults and achieve source authenticity and path compliance even if communication channels in the network are not reliable. RFL samples and verifies packets in each network entity so that the packet source can efficiently localize faults of packet forwarding by verifying the sampled packets. By leveraging packet acknowledgment, packet sampling based fault localization is not impacted by packet loss in the communication channels. In particular, RFL leverages a symmetric key distribution scheme to implement robust key distribution among different entities, which ensures that packet sources can always correctly fresh their keys to perform correct localization. Our security and theoretical analysis demonstrates the robustness of RFL protocol. We implement the RFL prototype on Click routers. The experiment results with the prototype demonstrate that RFL achieves more than 99.5% localization accuracy while incurring only 10% throughput degradation.

Understanding and Improving the Performance of Constructive Interference Using Destructive Interference in WSNs

The constructive interference (CI) phenomenon has been exploited by a number of protocols for providing energy-efficient, low-latency, and reliable data collection and dissemination services in wireless sensor networks. These protocols consider CI to provide highly reliable packet delivery. This has attracted attention to understand the working of CI; however, the existing works present inconsistent views. Furthermore, these works do not study in the real-world settings where the physical conditions of deployment and unreliable wireless channels also impact the performance of CI. Therefore, we study the phenomenon of CI, considering a receiver’s viewpoint and analyze the parameters that affect CI. We validate our arguments with results from extensive and rigorous experimentation in real-world settings. This paper presents comprehensive insights into the CI phenomenon. With the understanding, we develop the destructive interference-based power adaptation (DIPA), an energy-efficient and distributed algorithm, that adapts transmission power to improve the performance of CI. Since CI-based protocols cannot have an explicit acknowledgment packet, we make use of destructive interference on a designated byte to provide a feedback. We leverage this feedback to adapt transmission powers. We compared CI with and without DIPA in two real-life testbeds. On one testbed, we achieve around 25% lower packet losses while using only half of its transmission power for 64-B packets. On the other testbed, we achieve 25% lower packet losses while consuming only 47% of its transmission power for 128-B packets. Existing CI-based protocols can easily incorporate DIPA into them to achieve lower packet losses and higher energy efficiencies.