Design Of Active Queue Management Research Articles

Congestion control with AQM and dynamic quantisers

This study is concerned with the design of active queue management (AQM) subjected to quantisation errors. First, the authors will show here that quantisation errors exist when AQM experiences transmission control protocol (TCP) during the congestion. Second, a TCP/AQM model that takes into account quantisation errors is proposed – the considered quantisers are dynamic and have a scale parameter. Based on this model, stabilisation will be analysed in which the controller and the scaling parameters are obtained using the Lyapunov–Krassovskii functional method. Finally, Matlab simulation results are displayed to show the effectiveness of the proposed method.

Grey wolf optimizer based fuzzy-PI active queue management design for network congestion avoidance

<p>Congestion is one of the most important issues in communication networks which has attracted much research attention. To ensure a stable TCP network, we can use active queue management (AQM for early congestion detection and router queue length regulation. In this study, it was proposed to use the Grey Wolf Optimizer (GWO) algorithm in designing a fuzzy proportional integral (fuzzy-PI) controller as a novel AQM for internet routers congestion control and for achieving a low steady-state error and fast response. The suggested Fuzzy logic-based network traffic control strategy permit us to deploy linguistic knowledge for depicting the dynamics of probability marking functions and ensures a more accurate use of multiple inputs to depict the the network’s state. The possibility of incorporating human knowledge into such a control strategy using Fuzzy logic control methodology was demonstrated. The postulated controller was compared to proportion integral (PI) through several MATLAB simulation scenarios. The results indicated the stability of the postulated controller and its ability to attain a faster response in a dynamic network with varying network load and target queue length.</p>

Dynamic traffic aware active queue management using deep reinforcement learning

Traditional design of active queue management (AQM) assumes a fixed model at an operating point and lacks planning. AQMs like controlled delay provide some planning but are insensitive to dynamic traffic. In this Letter, the authors propose dynamic traffic aware AQM with deep reinforcement learning to expand the model on a grid of operating points and to add more planning. By learning the network parameter on the grid and the transitions between operating points with collected data, the fluid model of transmission control protocol dynamics is obtained. Planning on operating points is enhanced by value iterations. Evaluations show that the algorithm decreases queuing delay for dynamic traffic with more planning.

C2TCP: A Flexible Cellular TCP to Meet Stringent Delay Requirements

Since, current widely available network protocols/ systems are mainly throughput-oriented designs, meeting stringent delay requirements of new applications such as virtual reality and vehicle-to-vehicle communications on cellular network requires new network protocol/system designs. C2TCP is an effort toward that new design direction. C2TCP is inspired by in-network active queue management designs such as RED and CoDel and motivated by lack of a flexible end-to-end approach which can adapt itself to different applications’ QoS requirements without modifying any network devices. It copes with unique challenges in cellular networks for achieving ultra-low latency (including highly variable channels, deep per-user buffers, self-inflicted queuing delays, and radio uplink/downlink scheduling delays) and intends to satisfy stringent delay requirements of different applications while maximizing the throughput. C2TCP works on top of classic throughput-oriented TCP and accommodates various target delays without requiring any channel prediction, network state profiling, or complicated rate adjustment mechanisms. We have evaluated C2TCP in both real-world environment and extensive trace-based emulations and compared its performance with different TCP variants and state-of-the-art schemes including PCC-Vivace, Google’s BBR, Verus, Sprout, TCP Westwood, and Cubic. Results show that C2TCP outperforms all these schemes and achieves lower average delay, jitter, and 95th percentile delay for packets.

Novel Active Queue Management Scheme for Routers in Wireless Networks

Congestion stability and prevention is the main aim of any decent network traffic management scheme. The protocol that drives congestion control in IP networks, called The Transmission Control Protocol (TCP), is plagued by bandwidth underutilization when implemented on wireless networks. The management of network trunk queue size is the goal of this paper, along with its antecedent delay issues with Active Queue Management (AQM) algorithms that overcomes the bandwidth underutilization issue faced by TCP flows in wireless networks. Two adaptive TCP models, specifically built for wireless networks, were created. This made it possible to implement feedback control techniques in the chosen AQM design for queue management. The two AQM policies were created with the help of Model Predictive Control (MPC) and Self-Tuning Control (STC). A very thorough comparison was made between the developed AQM schemes and two Early Detection Controllers, namely, Random Early Detection (RED) and Fixed-Parameter Proportional Integral (PI). Under varying wireless network conditions, the results obtained from simulating the proposed queue management scheme in MATLAB® confirmed that the fixed PI and RED controllers were, by comparison, inferior in performance. Copyright © 2018 Praise Worthy Prize S.r.l. - All rights reserved.

An Adaptive AQM Algorithm Based on a Novel Information Compression Model

Because the bufferbloat phenomenon has significantly degraded the quality of service of interactive applications, there is pressing need for effective active queue management (AQM) strategies to be deployed at both intermediate devices and consumer edges. Existing models and AQM design methods usually lack sufficient consideration of heterogenous round-trip times, uncertain endpoint mechanisms, and time-varying network conditions. This paper proposes an innovative information compression model purely from routers’ perspective by evaluating the average effect an accepted/dropped packet has on the aggregated packet arriving rate. The proposed model is independent of round-trip time heterogeneity and specific endpoint protocols. A customized parameter identification algorithm and corresponding control strategy are developed to scale the regulating sensitivity of dropping probability adaptively. Simulation results demonstrate the performance improvements of the proposed algorithm in providing a good tradeoff between reducing the latency and maximizing the goodput, especially in large delay environments.

Effect of AQM-Based RLC Buffer Management on the eNB Scheduling Algorithm in LTE Network

With the advancement of the Long-Term Evolution (LTE) network and smart-phones, most of today’s internet content is delivered via cellular links. Due to the nature of wireless signal propagation, the capacity of the last hop link can vary within a short period of time. Unfortunately, Transmission Control Protocol (TCP) does not perform well in such scenarios, potentially leading to poor Quality of Service (QoS) (e.g., end-to-end throughput and delay) for the end user. In this work, we have studied the effect of Active Queue Management (AQM) based congestion control and intra LTE handover on the performance of different Medium Access Control (MAC) schedulers with TCP traffic by ns3 simulation. A proper AQM design in the Radio Link Control (RLC) buffer of eNB in the LTE network leads to the avoidance of forced drops and link under-utilization along with robustness to a variety of network traffic-loads. We first demonstrate that the original Random Early Detection (RED) linear dropping function cannot cope well with different traffic-load scenarios. Then, we establish a heuristic approach in which different non-linear functions are proposed with one parameter free to define. In our simulations, we demonstrate that the performance of different schedulers can be enhanced via proper dropping function.

Swarm intelligence based robust active queue management design for congestion control in TCP network

Active queue management (AQM) is an effective solution for the congestion control problem. It can achieve high quality of service (QoS) by reducing the packet dropping probability and network utilization. Three robust control algorithms are proposed in this paper in order to design robust AQM schemes: conventional controller, robust particle swarm optimization (PSO)‐based PID (proportional–integral–derivative) (PSOPID) controller, and robust ant‐colony optimization (ACO)‐based PID (ACOPID) controller. PSO and ACO methods are used to tune the PID controller parameters subject to constraints to achieve the required robustness of the network. Robust PSOPID and ACOPID controllers can achieve desirable time‐response specifications with a simple design procedure and low‐order controller in comparison to the conventional controller. Wide ranges of system parameters change are used to show the robustness of the designed controllers. The ability of the designed controllers to meet the specified performance is demonstrated using MATLAB 7. 11, (R2010b): The MathWorks, Inc.3 Apple Hill Drive Natick, MA USA. On the other hand, to verify the effectiveness of the designed controller, nonlinear simulation is performed using the NS2 package. Finally, it is shown by comparison that the proposed robust ACOPID can achieve more desirable performance than the PSOPID controller and the controllers that have been proposed in previous works. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Stable Queue Management in communication networks

Since Active Queue Management (AQM) was recommended by the Internet Engineering Task Force (IETF) as an efficient way to overcome performance limitations of Transmission Control Protocol (TCP), several studies have proven control theory to be a promising field for the design and analysis of congestion control in homogenous communication networks. AQM is gaining increased importance due to reports of buffer-induced latencies throughout the Internet. The increasing volume and diversity of traffic types (i.e., data, voice, and video) suggests that traffic management mechanisms, in general, and AQM schemes, specifically, must not only focus on the critical issue of congestion control but must also consider the QoS demands of heterogeneous traffic. However, to combine quality-of-service provisioning with congestion control, AQM design needs to be reconsidered. In this paper, we propose a state feedback controller design scheme for heterogeneous networks preserving the closed-loop system stability. Delay dependant stability conditions of the closed loop system are derived based on the Lyapunov-Krasovskii method. The proposed approach offers flexible choice of control parameters allowing the network administrator to control fairness and response time for each individual source node in a network of multiple links with different delay properties. The performance and robustness of the proposed controller were illustrated and analyzed using event-based computer simulations.

AQM router design for TCP network via input constrained fuzzy control of time-delay affine Takagi–Sugeno fuzzy models

In this article, Takagi–Sugeno (T–S) fuzzy control theory is proposed as a key tool to design an effective active queue management (AQM) router for the transmission control protocol (TCP) networks. The probability control of packet marking in the TCP networks is characterised by an input constrained control problem in this article. By modelling the TCP network into a time-delay affine T–S fuzzy model, an input constrained fuzzy control methodology is developed in this article to serve the AQM router design. The proposed fuzzy control approach, which is developed based on the parallel distributed compensation technique, can provide smaller probability of dropping packets than previous AQM design schemes. Lastly, a numerical simulation is provided to illustrate the usefulness and effectiveness of the proposed design approach.

Design of Active Queue Management for Robust Control on Access Router for Heterogeneous Networks

The Internet architecture is a packet switching technology that allows dynamic sharing of bandwidth among different flows with in an IP network. Packets are stored and forwarded from one node to the next until reaching their destination. Major issues in this integration are congestion control and how to meet different quality of service requirements associated with various services. In other words streaming media quality degrades with increased packet delay and jitter caused by network congestion. To mitigate the impact of network congestion, various techniques have been used to improve multimedia quality and one of those techniques is Active Queue Management (AQM). Access routers require a buffer to hold packets during times of congestion. A large buffer can absorb the bursty arrivals, and this tends to increase the link utilizations but results in higher queuing delays. Traffic burstiness has a considerable negative impact on network performance. AQM is now considered an effective congestion control mechanism for enhancing transport protocol performance over wireless links. In order to have good link utilization, it is necessary for queues to adapt to varying traffic loads. This paper considers a particular scheme which is called Adaptive AQM (AAQM) and studies its performance in the presence of feedback delays and its ability to maintain a small queue length as well as its robustness in the presence of traffic burstiness. The paper also presents a method based on the well-known Markov Modulated Poisson Process (MPP) to capture traffic burstiness and buffer occupancy. To demonstrate the generality of the presented method, an analytic model is described and verified by extensive simulations of different adaptive AQM algorithms. The analysis and simulations show that AAQM outperforms the other AQMs with respect to responsiveness and robustness.

Robust active queue management design: A loop-shaping approach

In this paper, a novel systematic design procedure is presented for robust active queue management (AQM). The congestion control law is obtained through an interactive loop-shaping process that manipulates the system frequency response to meet robust stability and performance requirements in the presence of uncertain network conditions. A sufficient condition leading to a satisfactory level of robust performance against high-frequency parasitics that naturally affect the desired requirements is then derived. A feature of the technique is that the uncertain phase information and round-trip time-delay that are inherent to the system dynamics are fully addressed in the design equations, resulting in minimal conservatism and/or over-design. Simulation results using the ns2 simulator are provided to illustrate the effectiveness of the proposed method.

The Effects of Active Queue Management and Explicit Congestion Notification on Web Performance

We present an empirical study of the effects of active queue management (AQM) and explicit congestion notification (ECN) on the distribution of response times experienced by users browsing the Web. Three prominent AQM designs are considered: the proportional integral (PI) controller, the random exponential marking (REM) controller, and adaptive random early detection (ARED). The effects of these AQM designs were studied with and without ECN. Our primary measure of performance is the end-to-end response time for HTTP request-response exchanges. Our major results are as follows. If ECN is not supported, ARED operating in byte-mode was the best performing design, providing better response time performance than drop-tail queueing at offered loads above 90% of link capacity. However, ARED operating in packet-mode (with or without ECN) was the worst performing design, performing worse than drop-tail queueing. ECN support is beneficial to PI and REM. With ECN, PI and REM were the best performing designs, providing significant improvement over ARED operating in byte-mode. In the case of REM, the benefit of ECN was dramatic. Without ECN, response time performance with REM was worse than drop-tail queueing at all loads considered. ECN was not beneficial to ARED. Under current ECN implementation guidelines, ECN had no effect on ARED performance. However, ARED performance with ECN improved significantly after reversing a guideline that was intended to police unresponsive flows. Overall, the best ARED performance was achieved without ECN. Whether or not the improvement in response times with AQM is significant, depends heavily on the range of round-trip times (RTTs) experienced by flows. As the variation in flows' RTT increases, the impact of AQM and ECN on response-time performance is reduced.We conclude that AQM can improve application and network performance for Web or Web-like workloads. In particular, it appears likely that with AQM and ECN, provider links may be operated at near saturation levels without significant degradation in user-perceived performance.

Design of robust active queue management controllers for a class of TCP communication networks

This paper describes the design of active queue management (AQM) controllers for a class of TCP communication networks. In TCP/IP networks, the packet-dropping probability function is considered as a control input. Therefore, a TCP AQM controller was modeled as a time-delayed system with a saturated input. The objective of the work described here was to design robust controllers capable of achieving the desired queue size and guaranteeing asymptotic stability of the operating point. To achieve this aim, we have proposed two control strategies, namely a static state feedback controller and an observer-based controller. By applying the Lyapunov–Krasovskii functional approach and the linear matrix inequality technique, control laws and delay-independent stability criteria for the AQM controllers were derived. The performance of the two control schemes was evaluated in various network scenarios via a series of numerical simulations. The simulation results confirm that the proposed schemes outperform other AQM schemes.