Additive Increase And Multiplicative Decrease Research Articles

Periodic solutions, chaos and bi-stability in the state-dependent delayed homogeneous Additive Increase and Multiplicative Decrease/Random Early Detection congestion control systems

The combination of Additive Increase and Multiplicative Decrease (AIMD) congestion control and Random Early Detection (RED) queue as a whole congestion control system plays a key role in the overwhelming success of the Internet. Thus it is important to investigate the periodic oscillations and complicated dynamics of the state-dependent delayed homogeneous Additive Increase and Multiplicative Decrease/Random Early Detection (AIMD/RED) congestion control system and its modified version fully in this paper. Firstly employing the semi-analytical method called as the harmonic balance method with alternating frequency/time (HB-AFT) domain technique, the approximate analytical expressions of periodic solutions of the generalized homogeneous-flow Additive Increase and Multiplicative Decrease/Random Early Detection (AIMD/RED) system with state-dependent round-trip delay are considered. We compare them with the results of numerical simulations by WinPP, they agree very well with each other. It demonstrates that the method employed here is versatile, valid, simple and effective. Then to the end of improving its modeling and performance, we modify the above model by taking an easy approximate dropping function. Furthermore, for the modified delayed homogeneous system, the approximate analytical expressions of periodic solutions are obtained accurately, and some complex dynamics are also presented. Four kinds of bi-stability, i.e., the coexistence of chaos and Period-3 solution, that of Period-1 and Period-2 solutions, that of Period-2 and Period-2 solutions, that of Period-4 and Period-2 solutions are disclosed. And a route to chaos, i.e., Period Doubling bifurcation to chaos, and the window of Period-3 to chaos are also discovered. The periodic oscillation can reduce the link utilization, induce the TCP stream synchronization services and further congestion. Chaotic oscillation may result in collapse. Therefore, all complex dynamical phenomena found in this paper are harmful and should be avoided. The obtained results can be very helpful for the researchers to have a better understanding of the mechanism of the network congestion control system, and they can select the parameters properly to improve the network stability and performance.

Smart application-aware IoT data collection

We present and experimentally evaluate procedures for efficient IoT data collection while achieving target requirements in terms of data accuracy, response time, energy, and privacy protection. Different strategies are considered because different IoT applications can have different requirements. Specifically, the accuracy-driven strategy adjusts the time period between consecutive measurements following an additive increase and multiplicative decrease (AIMD) scheme based on a target data accuracy, while the time-driven strategy adjusts the time period between measurement requests to achieve delay less than a given maximum delay between consecutive measurements. The energy-driven strategy considers both the data accuracy and the energy costs for the corresponding measurements. Finally, the privacy-driven strategy adds noise to measurements using differential privacy techniques. The experimental evaluation involves real temperature, humidity, and ozone (O3) measurements obtained from three testbeds through the FIESTA-IoT platform. Our results show that the AIMD adaptation of the measurement period is robust to different types of measurements from different testbeds, without having any tuning parameters. Also, the experimental results show the trade-offs between the target data accuracy and the number of measurements and between the target data accuracy and the corresponding energy costs. For the privacy-driven strategy, the results show that the addition of noise to the sensor measurements using differential privacy has a negligible effect on the aggregate statistics.

Autonomous Transmission Power Decision Strategy for Energy Efficient Operation of a Dense Small Cell Network

Smart interference management methods are required to enhance the throughput, coverage, and energy efficiency of a dense small cell network. In this paper, we propose a transmit power control for energy efficient operation of a dense small cell network. We cast the power control problem as a noncooperative game to satisfy the design requirement that small cells do not need any information exchange among them. We analyze the sufficient condition for the existence of a Nash equilibrium (NE) state of the proposed game. We also analyze that the NE state is unique by transforming the original nonlinear fractional programming problem into a nonlinear parametric programming problem. Through simulation studies, we verify our analysis results. In addition, we show that the proposed method achieves higher energy efficiency of a network and balances the energy efficiency among cells more evenly than the methods based on the AIMD (additive increase and multiplicative decrease) algorithm.

From adaptive control to variable structure systems – seeking harmony

From adaptive control to variable structure systems – seeking harmony

A decentralized adaptive algorithm for fair allocation of a shared resource

SummaryThis paper views the classical Chiu–Jain algorithm, originally proposed for congestion control of network links, as a decentralized algorithm for the fair allocation of a total of c units of a shared resource among n users. A new analysis is given of the general case of additive increase and multiplicative decrease (AIMD) dynamics, from the perspective of virtual equilibria and variable structure systems, leading to a better understanding of the Chiu–Jain algorithm, which is one example of AIMD dynamics. It is shown that the variable structure discrete dynamical system that describes the evolution of the share of each individual, starting from an arbitrary initial allocation, always attains a neighbourhood of the fair share (c/n) for each user, under the assumption that the latter is known. Subsequently, a new adaptive version of the algorithm, called adaptive AIMD, is described, with the same property of converging to the fair share, without assuming that it is known. Simulations that show the behaviour and advantages of the proposed adaptive AIMD adaptive algorithm are given. Copyright © 2015 John Wiley & Sons, Ltd.

Fast fairness convergence through fair rate estimation in Variable-structure congestion Control Protocol

Traditional Transmission Control Protocol (TCP) faces significant limitations such as unclear congestion implication, low utilization in high-speed networks, unstable throughput and limited fairness. In order to overcome such limitations, numerous research works have been done in effective congestion control algorithms. Among these, Variable-structure congestion Control Protocol (VCP) leverages only the existing two explicit congestion notification bits for network congestion feedback, yet achieves high utilization, low persistent queue length, negligible packet loss rate and reasonable fairness. However, VCP converges to fairness relatively slowly due to its large multiplicative decrease parameter. To address this problem, we propose an end-host based method for fast fairness convergence, namely VCP-FFC (VCP with fast fairness convergence). In each Additive Increase and Multiplicative Decrease (AIMD) epoch, VCP-FFC estimates a fair rate in end-hosts, and adjusts the congestion window according to the fair rate to achieve fast fairness convergence. We evaluate the performance of VCP-FFC over a wide range of network scenarios using NS2. Simulation Results show that VCP-FFC not only maintains the good properties of VCP, but also significantly accelerates fairness convergence. Dynamic analysis shows that VCP-FFC is asymptotically stable and converges to a unique stationary point, i.e. the fair rate share.

Stochastic backlog and delay bounds of generic rate-based AIMD congestion control scheme in cognitive radio sensor networks

Performance guarantees for congestion control schemes in cognitive radio sensor networks (CRSNs) can be helpful in order to satisfy the quality of service (QoS) in different applications. Because of the high dynamicity of available bandwidth and network resources in CRSNs, it is more effective to use the stochastic guarantees. In this paper, the stochastic backlog and delay bounds of generic rate-based additive increase and multiplicative decrease (AIMD) congestion control scheme are modeled based on stochastic network calculus (SNC). Particularly, the probabilistic bounds are modeled through moment generating function (MGF)-based SNC with regard to the sending rate distribution of CR source sensors. The proposed stochastic bounds are verified through NS2-based simulations.

An AIMD Distributed Control Law for Load Balancing in Content Delivery Networks

Content Delivery Networks (CDN) is the best for overcoming the inherited problems face by internet in modern days. The major idea at the basis of this technology is the delivery at edge points of the network, in proximity to the request areas, to advance the user’s perceived performance while off-putting the overheads. Literature shows that in Content Delivery Network how this demanding problem of defining and implementing an effective law for load balancing is model. But this system has some drawback, like even if the queue length of server is low they redirect loads to another server to only balance the overall load. Due to this request processing overhead and delay increases. Algorithm model in paper can help to reduce this delay by putting one equilibrium point to request queue. In CDN, the source adjusts its rate using a modified Additive Increase and Multiplicative Decrease (AIMD) algorithm. AIMD has been demonstrated to be sufficient and essential of efficiency and fairness under certain general conditions.

Enhanced AIMD-based decentralized residential charging of EVs

Moving from combustion engine to electric vehicle (EV)-based transport is recognized as having a major role to play in reducing pollution, combating climate change and improving energy security. However, the introduction of EVs poses major challenges for power system operation. With increasing penetration of EVs, uncontrolled coincident charging may overload the grid and substantially increase peak power requirements. Developing smart grid technologies and appropriate charging strategies to support the role out of EVs is therefore a high priority. In this paper, we investigate the effectiveness of distributed additive increase and multiplicative decrease (AIMD) charging algorithms, as proposed by Stüdli et al. in 2012, at mitigating the impact of domestic charging of EVs on low-voltage distribution networks. In particular, a number of enhancements to the basic AIMD implementation are introduced to enable local power system infrastructure and voltage level constraints to be taken into account and to reduce peak power requirements. The enhanced AIMD EV charging strategies are evaluated using power system simulations for a typical low-voltage residential feeder network in Ireland. Results show that by using the proposed AIMD-based smart charging algorithms, 50% EV penetration can be accommodated, compared with only 10% with uncontrolled charging, without exceeding network infrastructure constraints.

An Improved AIMD Algorithm for Wireless Cellular Video Transmission

This paper proposes a novel additive increase and multiplicative decrease (AIMD) algorithm for wireless video transmission over cellular networks. The goal of this new algorithm is to improve the bandwidth utilization efficiency without degrading its fairness potential. To address this issue, it increases the regulating segment during the fast-recovery stage, and uses a time-window-based adjusting scheme to filter the short-time-slot bandwidth fluctuation. Simulation results show that the proposed algorithm has faster bandwidth recover speed and less transmission rate fluctuation than that of the traditional AIMD algorithm.

A Study of Fair Bandwidth Sharing with AIMD-Based Multipath Congestion Control

The multi-homed capability offers a good opportunity to explore multipath transmission. To ensure fair bandwidth sharing between multipath flows and legacy single-path flows, congestion control is an essential mechanism at the transport layer to regulate traffic flows for bandwidth consumption. However, in a multipath scenario, the congestion control algorithm of the dominant transport control protocol (TCP) may result in too aggressive behavior. In this paper, we consider the generic congestion control principle of additive increase and multiplicative decrease (AIMD) and investigate two AIMD-based multipath congestion control solutions. We derive the conditions for AIMD parameters to ensure TCP-friendliness and satisfy two constraints for fair bandwidth sharing between multipath and single-path flows. Simulation results demonstrate that the AIMD-based multipath solutions well achieve the fairness goals.

Differentiated Congestion Management of Data Traffic for Data Center Ethernet

This paper aims at designing a congestion and priority solution for Ethernet congestion management. Following the popular approach that uses a cooperation of an Additive Increase and Multiplicative Decrease (AIMD) based rate limiter and Explicit Congestion Notification (ECN) active queue management to combat congestions in Ethernet, the proposal considers differentiated AIMD settings for rate limiters to achieve congestion control differentiation for traffic of different priorities. We illustrate that while the operations of AIMD and ECN are independent, by using different AIMD settings, we can achieve differentiated control of bandwidth utilization. We develop a control theoretic analytical model to study the effectiveness of our proposed method. Moreover, we implement our proposed method in OMNET++ simulator to conduct simulation experiments. Our analytical and simulation results both indicate the effectiveness of bandwidth ratio differentiation.

Research of Multimedia Data Transmission Based on UDP

The article focuses on the research of a reliable data transmission extension protocol -- UDT based on UDP, the related implementation method and transmission control method of multimedia data real-time and reliable transmission, the improvement to algorithm of its related methods in specific applications; as well as the improvement to AIMD (Additive Increase and Multiplicative Decrease) congestion controlling algorithm, proposing DAIMD congestion controlling algorithm; the sending rate increment is changed from the constant quantity to the variable quantity which continuously reduces with the continuous increase of the sending rates, so it not only makes a more rational use of limited network bandwidth, also reduces the larger oscillation in the network data transmission; the improvement of validation mechanisms, propose validation mechanisms based on the combination of time and data packets numbers, and improve the efficiency of data transmission. When the multimedia data network transmits, the transmitter and receiver need to identify a network transmission protocol. According to the above analysis, UDP is a simple transmission level protocol, non-connection-oriented, and itself does not provide data retransmission and confirmation, therefore adopting UDP as the network transmission protocol can improve the data transmission efficiency, besides UDP supports the webcast function, suitable for multimedia data network transmission [1]. However, the characteristic of multimedia data network transmission requests the network transmission protocol can handle the phenomenon of delay and vibration in the transmission process; can handle bursting multimedia data transmission; can judge the network condition according to the reception quality of the receiver and the sender can make the appropriate response; can ensure the reliability of multimedia data network transmission and so on. Features of UDP its own design make it deal with such situations not very well, also UDP limits the sending data packet size each time; when the multimedia data network transmits, a video data often exceed this limit. Therefore, according to the previous analysis of multimedia data network transmission characteristics and technical requirements, this article studies the reliable data transmission extension protocol -- UDT based on UDP, and improves the related algorithm and control mechanism in the protocol to make it more suitable for the multimedia data network transmission in the embedded video surveillance system.

Adaptive Packetization for Conversational Video Service over IEEE 802.11 WLANs with Hidden Terminals

For IEEE 802.11-based wireless local area networks (WLANs), due to inherent random access mechanisms, it is very challenging to provision video services, which are subject to very stringent quality-of-service (QoS) constraints. Collision and fading are two main sources of packet loss in WLANs and as such, both are affected by the packetization at the medium access control (MAC) layer. While a larger packet is preferred to balance protocol header overhead, a shorter packet is less vulnerable to packet loss due to channel fading errors or staggered collisions in the presence of hidden terminals. In this paper, we exploit estimate of collision probabilities to adapt packetization for video frames. We first show analytically that the effective throughput is a unimodal function of packet size when considering both channel fading and staggered collisions. We then design an additive increase and multiplicative decrease (AIMD) packetization strategy which adjusts the MAC-layer packet size based on local estimate of staggered collision probability. It is demonstrated that the proposed approach can greatly improve the effective throughput of WLAN and reduce video frame transfer delay.

Receiver-Assisted Congestion Control to Achieve High Throughput in Lossy Wireless Networks

Many applications would require fast data transfer in high-speed wireless networks nowadays. However, due to its conservative congestion control algorithm, Transmission Control Protocol (TCP) cannot effectively utilize the network capacity in lossy wireless networks. In this paper, we propose a receiver-assisted congestion control mechanism (RACC) in which the sender performs loss-based control, while the receiver is performing delay-based control. The receiver measures the network bandwidth based on the packet interarrival interval and uses it to compute a congestion window size deemed appropriate for the sender. After receiving the advertised value feedback from the receiver, the sender then uses the additive increase and multiplicative decrease (AIMD) mechanism to compute the correct congestion window size to be used. By integrating the loss-based and the delay-based congestion controls, our mechanism can mitigate the effect of wireless losses, alleviate the timeout effect, and therefore make better use of network bandwidth. Simulation and experiment results in various scenarios show that our mechanism can outperform conventional TCP in high-speed and lossy wireless environments.

Bounds estimation and practical stability of AIMD/RED systems with time delays

The Additive Increase and Multiplicative Decrease (AIMD) congestion control algorithm of TCP deployed in the end systems and the Random Early Detection (RED) queue management scheme deployed in the intermediate systems contribute to Internet stability and integrity. Previous research based on the fluid-flow model analysis indicated that, with feedback delays, the TCP/RED system may not be asymptotically stable when the time delays or the bottleneck link capacity becomes large [3]. However, as long as the system operates near its desired equilibrium, small oscillations around the equilibrium are acceptable, and the network performance (in terms of efficiency, loss rate, and delay) is still satisfactory. In this paper, we study the practical stability of AIMD/RED system with feedback delays and with both homogeneous and heterogeneous flows. We obtain theoretical bounds of the flow window size and the RED queue length, as functions of the number of flows, link capacity, RED queue parameters, and AIMD parameters. Numerical results with Matlab and simulation results with NS-2 are given to validate the correctness and demonstrate the tightness of the derived bounds. The analytical and simulation results provide important insights on which system parameters contribute to higher system oscillations and how to set parameters (such as buffer size and queue management parameters) to ensure system efficiency with bounded delay and loss. Our results can also help to predict and control the system performance for Internet with higher data rate links multiplexed with heterogeneous flows with different parameters.

A study of deploying smooth‐ and responsive‐TCPs with different queue management schemes

AbstractWhile there exist extensive research works on congestion control and active queue management, or the joint dynamics of a congestion control strategy with the random early detection (RED) algorithm, little has been done on the interactions between different window adjustment strategies and different queue management schemes such as DropTail and RED. In this paper, we consider a spectrum of TCP‐friendly additive increase and multiplicative decrease (AIMD) parameters. At the one end of this spectrum, smooth‐TCP enhances smoothness for multimedia applications by reducing the window decrease ratio upon congestion, at the cost of the additive increase speed and the responsiveness to available bandwidth. At the other end, responsive‐TCP enhances the responsiveness by increasing the additive increase speed, at the cost of smoothness. We investigate the network dynamics with various combinations of AIMD parameters and queue management schemes, under different metrics. The investigation is conducted from the deployment (especially incremental deployment) point of view. We discussed the impact of the interactions on the goodput, fairness, end‐to‐end delay, and its implications to energy consumption on mobile hosts. Copyright © 2008 John Wiley & Sons, Ltd.

Stability analysis of multiple-bottleneck networks

A TCP/RED (Transmission Control Protocol/Random Early Detection) system with multiple-bottleneck links could be unstable even if its system parameters are set the same as those in a stable single-bottleneck system [D. Bauso, L. Giarre, G. Neglia, Active queue management stability in multiple bottleneck networks, IEEE ICC’04, vol. 4, June 2004, pp. 2267–2271]. In this paper, we study the stability of more general AIMD (Additive Increase and Multiplicative Decrease)/RED system with multiple bottlenecks that may incur non-negligible packet losses. We develop a general mathematical model to analyze network stability for both delay-free and delayed AIMD/RED systems. Sufficient conditions for the asymptotic stability of multiple-bottleneck systems with heterogeneous delays are derived by appealing to Lyapunov stability theory with Lyapunov–Razumikhin conditions, and these conditions can be easily assessed by using LMI (Linear Matrix Inequality) Toolbox. Numerical results with Matlab and simulation results with NS-2 are given to validate the analytical results.

Enabling network calculus-based simulation for TCP congestion control

In this paper, we propose to speed up the simulation performance for TCP-operated networks by incorporating network calculus-based models in a simulation framework. In the simulation framework, we describes the operational properties of TCP congestion control, additive increase and multiplicative decrease (AIMD) and slow start, together with the queue discipline in the domain of network calculus. In order to determine network calculus models for TCP congestion, we first devise a simple TCP throughput model which approximately determines the range of per-flow throughput that one TCP can attain in a given interval, given the number of packet losses in the interval. We then exploit the TCP model to define a collection of network calculus theorems that regulate TCP flows in the range between the upper- and lower-limits on the TCP per-flow throughput in the corresponding interval. Finally, we incorporate the derived rules (theorems) into ns-2 to obtain a network calculus-based (NC-based) simulation, and carry out both the NC-based and the packet-level simulation to evaluate the performance gain and accuracy of the NC-based simulation, where the former is represented in perspective of the execution time (wall time) incurred in conducting the simulations and the later is evaluated in terms of the difference between results obtained in both the packet-level and NC-based simulation. The simulation results indicate that an order of magnitude or more (maximally 30 times) improvement in the execution time is achieved and the performance improvement becomes more salient as the network size increases in perspective of network-link capacities and the number of flows. The discrepancy observed between the NC-based simulation and the packet-level simulation, on the other hand, is minimally 1-2% and maximally 8-12% in a wide spectrum of network topologies and traffic loads. Additionally the results also indicate that the NC-based simulation outperforms a fluid-model-based simulation realized with the use of the time-stepped hybrid simulation technique, and that the performance improvement of the NC-based simulation is still held in IEEE 802.11-based wireless networks and also immune to the type of the simulation platform consisting of ns-2, operating system, and hardware specification.

Interaction Between MIMD-Poly and PIPD-Poly Algorithms and Other TCP Variants in Multiple Bottleneck TCP Networks

This paper introduces and analyzes a class of non-linear congestion control algorithms called polynomial congestion control algorithms. They generalize the Additive Increase and Multiplicative Decrease (AIMD) algorithms used for Transmission Control Protocol (TCP) connections. These algorithms provide additive increase using a polynomial of the inverse of the current window size and provide multiplicative decrease using the polynomial of the current window size. There are infinite numbers of TCP-compatible polynomial algorithms by assuming a polynomial of a different order. This paper analyzes the interaction between the two models (Multiplicative Increase and Multiplicative Decrease/MIMD-Poly and Polynomial Increase and Polynomial Decrease/PIPD-Poly) of these generalized algorithms, for wired (with unicast and multicast) and wireless TCP networks. TCP compatibility of these algorithms is evaluated using the simulations of the implementations of the proposed two models. Simulations are done using ns2, a discrete event simulator. The model MIMD-Poly is proved to be TCP compatible. The results of the simulation are compared with TCP variants, such as TCP/Tahoe, TCP/Reno, TCP/New Reno and TCP/Vegas. The comparison shows that both algorithms perform better in terms of throughput.