Transmission Control Protocol NewReno Research Articles

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.

TCP-CLD: Cross-Layer Design for Improving TCP Performance Over Cognitive Radio Networks

Due to the development and evolution in Cognitive Radio Networks (CRNs), the performance of Transmission Control Protocol (TCP) over CRN has become a crucial factor. TCP ensures the reliable end-to-end delivery of data, which is very important for the quality of service (QoS) requirements. TCP performance is severely affected by channel switching and channel availability in CRNs. The frequent occurrence of such events is due to CRNs nature which unnecessarily reduces the transmission rate which results in degrading the overall performance. In this paper, the authors investigate the limitations of using TCP NewReno (i.e., standard TCP) over CRNs, and further propose a cross-layer-design protocol based on an interaction between transport layer and lower layers to improve TCP performance over CRNs. The design is called Cross-Layer Design for TCP (TCP-CLD). It primarily aims at improving the TCP performance over CRNs via controlling and adapting a few selected TCP parameters. Specifically, the authors propose freezing the data transmission and re-transmission timeout (RTO) of TCP during the time of channel switching and channel unavailability. In addition, the authors update the size of congestion window (cwnd) of TCP based on the bandwidth and buffer size of relay nodes. Moreover, in the case of channel switching, the authors update the Round Trip Time (RTT) of TCP based on the new route delay. Simulation experiments have been conducted using ns-2 network simulator tool whereas results show that the proposed design achieves a significant performance improvement compared with the standard TCP NewReno protocol and the other known protocol, namely, TCP-CRAHN.

Performance Evaluation of Reactive Routing Protocols in MANETs in Association with TCP Newreno

We inspect the performance of TCP NewReno protocol for data transfer in Mobile Ad hoc networks (MANETs). Dynamic Source Routing (DSR) protocols and AdHoc On-demand Distance Vector (AODV) are standard reactive routing protocols widely used in MANETs. In addition we also have to consider Transmission Control Protocol (TCP) as essential for MANETs since it is one of the widely used internet protocol for dependable data transmission. TCP has its variants namely TCP Reno, TCP NewReno , TCP Vegas and TCP SACK. In this paper we are evaluating the performance of DSR and AODV in association with TCP Newreno with respect to various parameters such as Average throughput, instant throughput, residual energy, packet delivery ratio. The ns-2 network simulator was used for simulation.

Improving TCP Performance in Vehicle-To-Grid (V2G) Communication

On a connected car, the performance of Internet access will significantly affect the user experience. For electric cars that use vehicle-to-grid (V2G) communication to interact with the Internet during charging, the charge cable quality poses a challenge to the V2G communication. Specifically, the performance of Transmission Control Protocol (TCP), the transport protocol that most Internet applications use, may suffer due to the high noise and consequent errors that the charge cable presents. Currently, TCP NewReno is the TCP implementation that ISO 15118 standard stipulates for the V2G communication. However, its congestion control algorithm has been designed for the general Internet environment where congestion, not link errors, account for most of packet losses. Indeed, we confirm that the throughput of TCP NewReno rapidly degrades as the error rate increases on the charge cable. Specifically, we show that other TCP variants such as TCP Illinois far exceeds TCP NewReno in both lossy and non-lossy link environments. Finally, we propose how to configure TCP NewReno parameters to make it achieve the throughput comparable to other TCP variants on V2G communication environments, regardless of the link quality presented by the charging cable.

Performance Evaluation of TCP Vegas over TCP Reno and TCP NewReno over TCP Reno

In the Transport layer, there are two types of Internet Protocol are worked, namely- Transmission Control Protocol (TCP) and User datagram protocol (UDP). TCP provides connection oriented service and it can handle congestion control, flow control, and error detection whereas UDP does not provide any of service. TCP has several congestion control mechanisms such as TCP Reno, TCP Vegas, TCP New Reno, TCP Tahoe, etc. In this paper, we have focused on the behavior performance between TCP Reno and TCP Vegas, TCP New Reno over TCP Reno, when they share the same bottleneck link at the router. For instigating this situation, we used drop-tail and RED algorithm at the router and used NS-2 simulator for simulation. From the simulation results, we have observed that the performance of TCP Reno and TCP Vegas is different in two cases. In drop tail algorithm, TCP Reno achieves better Performance and throughput and act more an aggressive than Vegas. In Random Early Detection (RED) algorithm, both of congestion control mechanism provides better fair service when they coexist at the same link. TCP NewReno provides better performance than TCP Reno.

Performance analysis of different architectures and TCP congestion-avoidance algorithms using WMN-GA simulation system

In this paper, we evaluate the performance of two Wireless Mesh Networks (WMNs) architectures considering throughput, delay, jitter and fairness index metrics. For simulations, we used ns-3, Distributed Coordination Function (DCF) and Optimized Link State Routing (OLSR). We compare the performance of WMN for different Transmission Control Protocol (TCP): Tahoe, Reno and NewReno considering normal and uniform distributions of mesh clients by sending multiple Constant Bit Rate (CBR) flows in the network. The simulation results show that for normal and uniform distributions and both WMN architectures, the PDR values are almost the same. For Hybrid WMN, the throughput of TCP NewReno is good, but for I/B WMN, the throughput of TCP Tahoe is higher than other algorithms. For normal distribution, the delay and jitter of I/B WMN are lower compared with Hybrid WMN, while for uniform distribution, the delay and jitter of TCP NewReno are a little bit lower compared with other algorithms. The fairness index of normal distribution is higher than uniform distribution.

Characterizing End-to-End Delay Performance of Randomized TCP Using an Analytical Model

TCP (Transmission Control Protocol) is the main transport protocol used in high speed network. In the OSI Model, TCP exists in the Transport Layer and it serves as a connection-oriented protocol which performs handshaking to create a connection. In addition, TCP provides end-to-end reliability. There are different standard variants of TCP (e.g. TCP Reno, TCP NewReno etc.)which implement mechanisms to dynamically control the size of congestion window but they do not have any control on the sending time of successive packets. TCP pacing introduces the concept of controlling the packet sending time at TCP sources to reduce packet loss in a bursty traffic network. Randomized TCP is a new TCP pacing scheme which has shown better performance (considering throughput, fairness) over other TCP variants in bursty networks. The end-to-end delay of Randomized TCP is a very important performance measure which has not yet been addressed. In the current high speed networks, it is increasingly important to have mechanisms that keep end-to-end to delay within an acceptable range. In this paper, we present the performance evaluation of end-to-end delay of Randomized TCP. To this end, we have used an analytical and a simulation model to characterize the end-to-end delay performance of Randomized TCP.

Improving TCP Performance in Wireless Networks by Detection and Avoidance of Spurious Retransmission Timeouts

Transmission Control Protocol (TCP) is a connection oriented, reliable delivery, transport layer protocol. The performance of TCP is degraded when it is used in wireless networks. This is mainly because of the basic assumption of TCP that any packet loss is an indication of congestion, which is not true in wireless links. The TCP performance in wireless network can be improved by differentiating the wireless losses from the congestion losses. Various Loss Differentiation Algorithms (LDAs) are used to identify whether the packet losses are due to congestion or due to wireless links. The accuracy of wireless loss discrimination and the accuracy of congestion loss discrimination have a trade-off relationship based on their own threshold. The detection information of LDA alone is not sufficient to improve the performance of TCP due to presence of Spurious Retransmission Timeouts (SRTO). In this paper, a novel cross-layer approach, TCP-DDA (TCPDetection, Differentiation and Avoidance) is proposed, wherein the packet losses are differentiated using cross-layer based LDA, SRTO is detected and steps are taken to avoid the SRTO. A new TCP mechanism that is capable of detecting and differentiating the loss of retransmitted packets is also proposed, thereby enhancing the performance of TCP over wireless networks. The work is evaluated using simulation, and the performance improvement is observed by comparing with the existing TCP NewReno.

TTAF: TCP Timeout Adaptivity Based on Fast Retransmit over MANET

Transmission Control Protocol (TCP) is one of the most widely deployed transport layer protocols. It responds to all packet losses, either due to congestion or link breakages, by invoking various congestion control mechanisms. All these mechanisms imply a reduction in the amount of transmitted data. Computing a proper value of the retransmission timeout (RTO) is a challenge for TCP. In mobile ad hoc networks (MANET), mobility and bit error cause a lot of packet losses which degrades TCP throughput. In this paper we introduce an adaptation of TCP Ne wReno in order to improve its performance during the fast recovery phase. Our adapted algorithm, which we called TTAF, does not rely only on round trip time samples but also takes into consideration fast retransmit events in tuning the value of RTO. A set of experiments have been conducted to evaluate the effect of TTAF over MANET with various mobility speed, traffic load, and bit error rates. Results have shown an improvement in TTAF throughput compared with that of TCP NewReno.

TCP Karak: A New TCP AIMD Algorithm Based on Duplicated Acknowledgements for MANET

Transmission Control Protocol (TCP) performance over MANET is an area of extensive research. Congestion control mechanisms are major components of TCP which affect its performance. The improvement of these mechanisms represents a big challenge especially over wireless environments. Additive Increase Multiplicative Decrease (AIMD) mechanisms control the amount of increment and decrement of the transmission rate as a response to changes in the level of contention on routers buffer space and links bandwidth. The role of an AIMD mechanism in transmitting the proper amount of data is not easy, especially over MANET. This is because MANET has a very dynamic topology and high bit error rate wireless links that cause packet loss. Such a loss could be misinterpreted as severe congestion by the transmitting TCP node. This leads to unnecessary sharp reduction in the transmission rate which could degrades TCP throughput. This paper introduces a new AIMD algorithm that takes the number of already received duplicated ACK, when a timeout takes place, into account in deciding the amount of multiplicative decrease. Specifically, it decides the point from which Slow-start mechanism should begin its recovery of the congestion window size. The new AIMD algorithm has been developed as a new TCP variant which we call TCP Karak. The aim of TCP Karak is to be more adaptive to mobile wireless networks conditions by being able to distinguish between loss due to severe congestion and that due to link breakages or bit errors. Several simulated experiments have been conducted to evaluate TCP Karak and compare its performance with TCP NewReno. Results have shown that TCP Karak is able to achieve higher throughput and goodput than TCP NewReno under various mobility speeds, traffic loads, and bit error rates.

TCP Performance in Mobile Ad hoc Networks

In this paper, we present a survey of TCP (Transmission Control Protocol) protocol for better performance in the MANET (Mobile Ad Hoc Network). After a short presentation of the main features of TCP, we give the most important problems from which TCP suffer in MANET. We present after that some approaches proposed in the literature in order to improve its performance. Our paper contains also a performance evaluation of TCP NewReno and TCP Vegas transport protocols under AODV and DSR routing protocols. The simulations are conducted under varying conditions of number of TCP connections, number of nodes and mobility.

Analytical modeling of Transmission Control Protocol NewReno using Generalized Stochastic Petri Nets

SUMMARYThis paper presents a novel analytical model of Transmission Control Protocol (TCP) using a generalized stochastic Petri net (GSPN). Extensive simulation work has been done for the performance evaluation of TCP NewReno protocol. In view of the limitations of the simulation technique, we present an analytical approach using GSPN. A GSPN is a useful mathematical tool that solves continuous time Markov chains for complex systems and evaluates the stationary behavior. In this paper, we analyze the slow‐but‐steady variant of TCP NewReno. The model captures the behavioral aspects of the slow start and the congestion avoidance phase together with the fast retransmit and recovery capabilities of TCP NewReno. Performance metrics such as throughput, goodput, and task completion time of the system are obtained. The effect of variation in the model parameters on the performance is studied. The results are validated using the network simulator, and their accuracy is verified by evaluating the confidence interval. The performance of the proposed model is compared with that of TCP Reno. The performance of the proposed model is also compared with one of the previous models. The numerical illustrations and comparison of the proposed technique with simulation validates the accuracy, efficiency, and competence of the GSPN technique. While GSPN modeling for TCP is investigated in depth for the TCP NewReno and TCP Reno variant in this paper, other protocols could be also analyzed similarly. Copyright © 2013 John Wiley & Sons, Ltd.

Compound TCP+: A Solution for Compound TCP Unfairness in Wireless LAN

In high-speed and long-distance networks, TCP NewReno, the most popular version of Transmission Con- trol Protocol (TCP), cannot achieve sufficient throughput owing to the inherent nature of the congestion control mech- anism of TCP. Therefore, in order to overcome this limitation, Compound TCP was proposed. Compound TCP can achieve a considerably higher throughput than TCP NewReno in high-speed and long-distance networks. The conges- tion control mechanism of Compound TCP consists of loss-based and delay-based congestion controls. However, in wireless LAN, the media access control used causes unfairness in the throughput among TCP connections. Compound TCP has the same type of congestion control as TCP NewReno; hence, it is expected that the problem will occur among Compound TCP connections. In this study, we evaluate the performance of Compound TCP for wireless LAN, and demonstrate that the throughput among Compound TCP connections becomes unfair. Then, we propose Compound TCP+, which implements a finer congestion control by detecting a state of slight congestion. Using simulation, we show that in wireless LAN, Compound TCP+ connections achieve fairness and share the bandwidth equally. We also demonstrate through simulation that Compound TCP+ achieves high throughput in a high-speed wired network.

TCP NCE: A unified solution for non-congestion events to improve the performance of TCP over wireless networks

In this article, we propose a unified solution called Transmission Control Protocol (TCP) for Non-Congestion Events (TCP NCE), to overcome the performance degradation of TCP due to non-congestion events over wireless networks. TCP NCE is capable to reduce the unnecessary reduction of congestion window size and retransmissions caused by non-congestion events such as random loss and packet reordering. TCP NCE consists of three schemes. Detection of non-congestion events (NCE-Detection), Differentiation of non-congestion events (NCE-Differentiation) and Reaction to non-congestion events (NCE-Reaction). For NCE-Detection, we compute the queue length of the bottleneck link using TCP timestamp and for NCE-Differentiation, we utilize the flightsize information of the network with a dynamic delay threshold value. We introduce a new retransmission algorithm called 'Retransmission Delay' for NCE-Reaction which guides the TCP sender to react to non-congestion events by properly triggering the congestion control mechanism. According to the extensive simulation results using qualnet network simulator, TCP NCE acheives more than 70% throughput gain over TCP CERL and more than 95% throughput improvement as compared to TCP NewReno, TCP PR, RR TCP, TCP Veno, and TCP DOOR when the network coexisted with congestion and non-congestion events. Also, we compared the accuracy and fairness of TCP NCE and the result shows significant improvement over existing algorithms in wireless networks.

A stochastic model for the behavior of multiple TCP NewReno sources over optical burst switching network

This work proposes a stochastic model to characterize the transmission control protocol (TCP) over optical burst switching (OBS) networks which helps to understand the interaction between the congestion control mechanism of TCP and the characteristic bursty losses in the OBS network. We derive the steady-state throughput of a TCP NewReno source by modeling it as a Markov chain and the OBS network as an open queueing network with rejection blocking. We model all the phases in the evolution of TCP congestion window and evaluate the number of packets sent and time spent in different states of TCP. We model the mixed assembly process, burst assembler and disassembler modules, and the core network using queueing theory and compute the burst loss probability and end-to-end delay in the network. We derive expression for the throughput of a TCP source by solving the models developed for the source and the network with a set of fixed-point equations. To evaluate the impact of a burst loss on each TCP flow accurately, we define the burst as a composition of per-flow-bursts (which is a burst of packets from a single source). Analytical and simulation results validate the model and highlight the importance of accounting for individual phases in the evolution of TCP congestion window.

Modelling the Performance of a Cross-Layer TCP NewReno-HARQ System

This paper presents an analytical model of a cross-layer communication system to enable improvement in the Transmission Control Protocol (TCP) over mixed wired and wireless Internet. The focus is on the quantitative performance evaluation of the interactions between TCP NewReno and a hybrid Automatic Repeat reQuest protocol (HARQ) in the link layer (LL) with a finite buffer size. The significant improvement in TCP NewReno throughput when HARQ adaptively selects its optimal settings according to explicit cross-layer information is shown. Through ns-2 simulations, it is demonstrated that this proposed analytical model accurately predicts the TCP-HARQ system performance.

Transport Protocol Throughput Fairness

Interest continues to grow in alternative transport protocols to the Transmission Control Protocol (TCP). These alternatives include protocols designed to give greater efficiency in high-speed, high-delay environments (so-called high-speed TCP variants), and protocols that provide congestion control without reliability. For the former category, along with the deployed base of ‘vanilla’ TCP – TCP NewReno – the TCP variants BIC and CUBIC are widely used within Linux: for the latter category, the Datagram Congestion Control Protocol (DCCP) is currently on the IETF Standards Track. It is clear that future traffic patterns will consist of a mix of flows from these protocols (and others). So, it is important for users and network operators to be aware of the impact that these protocols may have on users. We show the measurement of fairness in throughput performance of DCCP Congestion Control ID 2 (CCID2) relative to TCP NewReno, and variants Binary Increase Congestion control (BIC), CUBIC and Compound, all in “out-of-the box” configurations. We use a testbed and endto- end measurements to assess overall throughput, and also to assess fairness – how well these protocols might respond to each other when operating over the same end-to-end network path. We find that, in our testbed, DCCP CCID2 shows good fairness with NewReno, while BIC, CUBIC and Compound show unfairness above round-trip times of 25ms.

Interaction between radio link level truncated ARQ, and TCP in multi-rate wireless networks: a cross-layer performance analysis

A complete queueing model for radio link layer performance analysis is developed assuming adaptive modulation and coding (AMC) at the physical layer and truncated automatic repeat request (ARQ)-based error control at the link layer. From the model, queue length distribution and average queueing delay can be calculated. The average queueing delay is then used to estimate transmission control protocol (TCP) throughput performance using a fixed-point approach. Using the model, we are able to choose signal-to-noise ratio thresholds of different transmission modes for AMC at the physical layer for different persistence levels of ARQ at the link layer so that TCP throughput is maximized. We observe that channel correlation negatively impacts the TCP throughput performance. Also, throughput enhancement of TCP NewReno over TCP Reno is observed to be non-negligible only if no ARQ-based error recovery is employed at the link layer.

Novel evaluation method of TCP performance over satellite links

A novel and efficient method to evaluate the transmission control protocol (TCP) performance over satellite links is presented. A TCP module is divided into three functional blocks, namely data processing, congestion control and error control. The re-established TCP module is easy to update TCP congestion control strategy or error control strategy. With the proposed analysis approach, the interactions between different congestion control and error control mechanisms, as well as the performance of various combination protocols in satellite environments have been investigated. Simulation results obtained through a series of experiments have shown that SNACK-based error control strategy can perform well with any other congestion control strategy. The best performance can be achieved by TCP NewReno congestion control strategy and SNACK-based error control strategy.

An Extended Model for TCP Loss Recovery Latency with Random Packet Losses

It has been a very important issue to evaluate the performance of transmission control protocol (TCP), and the importance is still growing up because TCP will be deployed more widely in future wireless as well as wireline networks. It is also the reason why there have been a lot of efforts to analyze TCP performance more accurately. Most of these works are focusing on overall TCP end-to-end throughput that is defined as the number of bytes transmitted for a given time period. Even though each TCP's fast recovery strategy should be considered in computation of the exact time period, it has not been considered sufficiently in the existing models. That is, for more detailed performance analysis of a TCP implementation, the fast recovery latency during which lost packets are retransmitted should be considered with its relevant strategy. In this paper, we extend the existing models in order to capture TCP's loss recovery behaviors in detail. On the basis of the model, the loss recovery latency of three TCP implementations can be derived with considering the number of retransmitted packets. In particular, the proposed model differentiates the loss recovery performance of TCP using selective acknowledgement (SACK) option from TCP NewReno. We also verify that the proposed model reflects the precise latency of each TCP's loss recovery by simulations.