Performance Evaluation Of TCP Research Articles

Performance Evaluation of TCP and UDP Protocols under EPLAODV Rout- ing Protocol in Emergency Situations

Mobile ad hoc networks (MANETs) can easily be deployed in a disastrous situation. Mobile routing protocols provide efficient routing strategies in such situations to share critical and emergency-related information. Many researchers have designed various energy and link-aware routing protocols but research still needs improvement. This study focuses on and evaluates the performance of TCP and UDP transport layer protocols under the EPLAODV routing protocol in an emergency. Various emergency-related scenarios are designed and simulated in the NS-2 environment. Network traffic load, node mobility, and simulation time are the main parameters. It is observed from the results that the TCP performs better than UDP under EPLAODV in an emergency situation.

Right buffer sizing matters: Some dynamical and statistical studies on Compound TCP

Large and unmanaged router buffers could lead to an increase in queuing delays in the Internet, which is a serious concern for network performance and quality of service. Our focus is to conduct a performance evaluation of Compound TCP (C-TCP), in a regime where the router buffer sizes are small (i.e., independent of the bandwidth-delay product), and the queue policy is Drop-Tail. In particular, we provide buffer sizing recommendations for high speed core routers fed by well multiplexed TCP controlled flows. For this, we consider two topologies: a single bottleneck and a multi-bottleneck topology, under different traffic scenarios. The first topology consists of a single bottleneck router, and the second consists of two distinct sets of TCP flows, regulated by two edge routers, feeding into a common core router. We focus on some key dynamical and statistical properties of the underlying system. From a dynamical perspective, we first develop fluid models. A local stability analysis for these models yields a key insight: buffer sizes need to be dimensioned carefully, and smaller buffers favour stability. We also highlight that larger Drop-Tail buffers, in addition to increasing latency, are prone to inducing limit cycles in the system dynamics. These limit cycles in turn induce synchronisation among the TCP flows, which then results in a loss of link utilisation. We then empirically analyse some statistical properties of the bottleneck queues. These statistical analyses serve to validate an important modelling assumption: that in the regime considered, each bottleneck queue may be reasonably well approximated as either an M∕M∕1∕B or an M∕D∕1∕B queue. We also highlight that smaller buffers, in addition to ensuring stability and low latency, would also yield reasonable system-wide performance, in terms of throughput and flow completion times.

Performance Evaluation of UDP, DCCP and TCP in Congested Wired Networks

Communication through the internet is one of the dominant methods of exchanging information. TCP and UDP are the transport layer protocols responsible for transit of nearly all Internet communications. Due to the growth of real-time audio and video applications, UDP is being used more frequently as a transport protocol, but unlike TCP, UDP has no mechanism for congestion control leading to wasted bandwidth and poor performance, so the DCCP protocol has appeared as a replacement for UDP. In this article, the author performs some simulations using NS2 for Drop Tail and RED queuing models to evaluate the performance of TCP, UDP, DCCP CCID2, and DCCP CCID3 protocols in congested wired networks. The performance metrics used are throughput, end to end delay, number of sent and lost packets. The obtained results show that the DCCP CCID2 performs the best throughput with the minimum of delay as compared to UDP, TCP, and DCCP CCID3.

Performance Evaluation of Multipath TCP Scheduling Algorithms

One of the goals of 5G is to provide enhanced mobile broadband and enable low latency in some use cases. To achieve this aim, the Internet Engineering Task Force has proposed the Multipath TCP by utilizing the feature of dual connectivity in 5G, where a 5G device can be served by two different base stations. However, the path heterogeneity between the 5G device and the server may cause a packet out-of-order problem. The researchers proposed a number of scheduling algorithms to tackle this issue. This paper introduces the existing algorithms, with the aim to make a thorough comparison between the existing scheduling algorithms and provide the guidelines for designing new scheduling algorithms in 5G, we have conducted an extensive set of emulation studies based on the real Linux experimental platform. The evaluation covers a wide range of network scenarios to investigate the impact of different network metrics, namely, RTT, buffer size, and file size on the performance of existing widely deployed scheduling algorithms.

On the Throughput Performance of TCP Cubic in Millimeter-Wave Cellular Networks

In this paper, we study a cross-layer analysis framework for the performance evaluation of TCP over millimeter-Wave (mmWave) fading channels in the fifth-generation (5G) cellular networks, when the truncated incremental redundancy hybrid automatic repeat request (IR-HARQ) scheme and adaptive modulation and coding (AMC) are employed. Specifically, the throughput performance of TCP Cubic, which is one of the most widely deployed TCP variants in the Internet, is investigated. For this purpose, the mmWave fading channel, approximated by Nakagami-m distribution, is captured by a finite-state Markov chain (FSMC) to develop a transmission loss model. A loss-based TCP model, which is analyzed based on the transmission loss model, is then used to analytically derive the TCP throughput performance. The numerical results quantitatively show the effect of different parameters/settings of AMC, IR-HARQ, blockages and mmWave fading channels on the TCP performance and support the optimal selection of parameters to maximize the system throughput. Monte Carlo simulations are also performed to validate the analytical results.

MCubic(Multipath Cubic)의 설계, 구현 및 다중 경로 TCP의 성능 평가에 관한 연구

MCubic(Multipath Cubic)의 설계, 구현 및 다중 경로 TCP의 성능 평가에 관한 연구

Performance evaluation of TCP over software-defined optical burst-switched data centre network

In this paper, we consider the performance of TCP when used in data centre networks (DCNs) featuring optical burst switching (OBS) using two-way reservation. The two-way reservation is not suitable in wide-area OBS networks due to high bandwidth-delay product (BDP). The burst loss using traditional methods of one-way reservation can be mistakenly interpreted by the TCP layer as congestion instead of contention in OBS network, leading to serious degradation of the TCP performance. The reduced BDP in DCNs allows the use of two-way reservation that results in zero burst loss. The modelled architecture features fast optical switches in a single hop topology. We apply different workloads with various burst assembly parameters to evaluate the performance of TCP. Our results show significant improvement in TCP performance as compared to traditional methods of OBS as well as to a conventional electronic packet switching DCN.

TCP performance evaluation over backpressure-based routing strategies for wireless mesh backhaul in LTE networks

Wireless redundant networks are expected to play a fundamental role to backhaul dense LTE networks. In these scenarios, backpressure-based routing strategies such as BP-MR can exploit the network redundancy. In this paper, we perform an exhaustive performance evaluation of different TCP variants over an LTE access network, backhauled by various routing protocols (including per-packet and per-flow BP-MR variants and a static alternative, OLSR) over two different wireless topologies: a regular mesh and an irregular ring-tree topology. We compare the performance of different TCP congestion control algorithms based on loss (NewReno, Cubic, Highspeed, Westwood, Hybla, and Scalable) and delay (Vegas) under different workloads. Our extensive analysis with ns-3 on throughput, fairness, scalability and latency reveals that the underlying backhaul routing scheme seems irrelevant for delay-based TCPs, whereas per-flow variant offers the best performance irrespective of any loss-based TCP congestion control, the most used in the current Internet. We show that BP-MR per-flow highly reduces the download finish time, if compared with OLSR and BP-MR per-packet, despite showing higher round-trip-time.

Steady-state performance evaluation of Linux TCPs versus TCP wave over leaky satellite links

Internet access is becoming even more heterogeneous, including different wireless backhauling links, with Ka-band satellites as a possible alternative. Since communication path is unknown a priori, adoption of PEP solutions to optimize TCP performance over satellite is discouraged to allow dynamic network reconfigurations. To opposite, an end-to-end TCP performance evaluation on such a challenging scenario, with possible large latency and transmission losses, is herein considered of paramount importance. Several TCP variants exist to tackle different aspects of communication networks. In Linux, the different TCP congestion control schemes differ from the theoretical formulations and RFC specifications, introducing a varying set of optimizations and options. This aspect makes difficult to identify a standard/reference TCP version for the proposed scenario, while testing with the real protocol stacks is deemed necessary to obtain consistent results. In addition, an innovative end-to-end TCP, namely TCP Wave, is introduced to replace the traditional window-based transmission with a burst-based strategy, representing a valid alternative to Linux TCP. To offer a fair, realistic and comprehensive evaluation, we configured a simulation setup where different Linux TCPs can be run within ns-3 network simulator and compared with TCP Wave.

Performance Evaluation of TCP and DCCP Protocols in Mobile Ad-Hoc Networks (MANETS)

Flow control, end-to-end (EED) delay, throughput, and energy consumptions are important factors of real-time and multimedia communication in mobile ad-hoc networks (MANET’s). It has a characteristic of the dynamic flow of data communication among the various users without using wired technologies. Due to this dynamic structure of MANNETS, most of its energy is consumed in route searching and packet retransmission. In addition, a problem of energy consumption may also occur due to network congestion and traffic flow control. In general, UDP is used for real-time communication but this protocol is unable to control the traffic flow properly. Therefore, a new protocol is developed for this purpose called datagram congestion control protocol (DCCP) used in those networks, which has an increasing number of multimedia traffic, and real-time flow. In this research work, major performance metrics with the issue of power usage of the TFRC and TCP like DCCP protocols are evaluated.

Multi-path TCP performance evaluation in dual-homed (wired/wireless) devices

Multipath TCP is a major extension of TCP, designed for leveraging the increasing availability of multiple interfaces in end hosts, on one side, and the existence of diverse Internet paths between hosts, on the other. This paper proposes a measurement methodology and provides a first evaluation, based on real Internet experiments, of the user benefit of using MPTCP instead of TCP in devices with multiple wireless/wired networking interfaces. We focus on bandwidth utilization and file transfer delays. Our experiments, on a testbed with two disjoint paths connecting a server and a dual-homed probe, indicate that MPTCP is able, in most cases, to take advantage of additional bandwidth with limited cost in terms of delay, but also show that the MPTCP bandwidth benefit substantially degrades when the interfaces have very different bandwidth capacities.

Coupled IEEE 802.11ac and TCP performance evaluation in various aggregation schemes and Access Categories

We investigate the Throughput of a TCP connection over an IEEE 802.11ac channel using the various aggregation schemes and Access Categories defined in this standard. We present an analytical model to compute the Throughput based on a Markov chain. The model is verified by simulation. This research has several outcomes. First, it assists in defining the optimal TCP Upload and Download working points, i.e. the optimal amount of aggregation, in every Access Category. Second, it is found that the Best Effort and Video Access Categories yield the largest Throughputs. In addition, the great amount of aggregation in Two-Level aggregation cancels the priority that one side of the connection has in accessing the channel in the Video and Voice Access Categories.

TCP and UDP-based performance evaluation of proactive and reactive routing protocols using mobility models in MANETS

User datagram protocol UDP and transmission control protocol TCP are two popular transport layer protocols in infrastructure networks. The behaviour of these transport layer protocol with different mobility models and routing protocols is still not very clear. In this article, we have compared the performance of user datagram protocol UDP and transmission control protocol TCP in mobile ad hoc network MANET for optimised link state routing OLSR, and temporarily ordered routing algorithm TORA routing protocols with different mobility models like random waypoint, reference point group, and Manhattan mobility models. We have done simulations in NS2 to analyse results using the performance metrics, such as throughput, packet delivery ratio, and end-to-end delay by for different types of data traffic and mobility models. The MANET performance is analysed under the effect of simulation time, number of nodes, and speed of mobile nodes. Our work indicates that TCP performs well for throughput in some mobility model and different routing protocols than UDP. The results presented in this paper clearly indicate that the different protocols behave differently under different parameters.

APPLICATION OF NEWTON RAPHSON ALGORITHM FOR OPTIMIZING TRANSMISSION CONTROL PROTOCOL PERFORMANCE

Wireless networks are growing rapidly. TCP is the most widely-used protocol on Internet and so optimizing TCP performance is very important for fast efficient data transfer. The different existing TCP variants and solutions they have not been analyzed together to identify the bottlenecks in wireless networks. TCP has a major problem in its congestion control algorithm which does not allow the flow to achieve the full available bandwidth on fast long-distance links. This problem has been studied in this study using a new high speed congestion control TCP protocol based on the Newton Raphson algorithm This study further analyses involving six TCP performance evaluation constraints namely, TCP full bandwidth utilization, throughput, packet loss rate, fairness in sharing bandwidth, friendliness in short-RTT and long-RTT and these constraints are used to evaluate the proposed Newton Raphson Congestion Control (NRC-TCP) performance. This study shows that the proposed algorithm performs better compared with the other methods of application.

Evaluation of TCP Performance by Using High-Speed Communication Satellite WINDS and Large Earth Terminal

Evaluation of TCP Performance by Using High-Speed Communication Satellite WINDS and Large Earth Terminal

Performance Evaluation of TCP with Adaptive Pacing and LRED in Multihop Wireless Networks

Performance Evaluation of TCP with Adaptive Pacing and LRED in Multihop Wireless Networks

A model-driven emulation approach to large-scale TCP performance evaluation

Small-scale experiments are insufficient for a comprehensive study of congestion control protocols. Similarly, results obtained from pure simulation platforms without exercising real protocols and applications lack realism. Motivated by these reasons, we developed scalable virtualised evaluation environment for TCP (SVEET), a TCP performance evaluation testbed where real implementations of TCP variants can be accurately evaluated under diverse network configurations and workloads from real applications in large-scale network settings. It is our purpose to provide the research community a standard environment through which quantitative assessment regarding TCP behaviour can be drawn from large-scale experiments. In order to accomplish our goal, we adopted a novel model-driven emulation approach combining real-time simulation, machine and time virtualisation techniques. We validate the testbed via extensive experiments to assess its potentials and limitations. Additionally, we performed case studies involving real web, streaming and peer-to-peer applications. Our results indicate that SVEET can accurately model the behaviour of the TCP variants and support large-scale network scenarios.

NOBS: an ns2 based simulation tool for performance evaluation of TCP traffic in OBS networks

Performance evaluation of tcp traffic in obs networks has been under intensive study, since tcp constitutes the majority of Internet traffic. As a reliable and publicly available simulator, ns2 has been widely used for studying tcp/ip networks; however ns2 lacks many of the components for simulating optical burst switching networks. In this paper, an ns2 based obs simulation tool (nobs), which is built for studying burst assembly, scheduling and contention resolution algorithms in obs networks is presented. The node and link objects in obs are extended in nobs for developing optical nodes and optical links. The ingress, core and egress node functionalities are combined into a common optical node architecture, which comprises agents responsible for burstification, routing and scheduling. The effects of burstification parameters, e.g., burstification timeout, burst size and number of burstification buffers per egress node, on tcp performance are investigated using nobs for different tcp versions and different network topologies.

Performance evaluation of high speed TCP over optical burst switching networks

Study of TCP performance over OBS networks has been an important problem of research lately and it was found that due to the congestion control mechanism of TCP and the inherent bursty losses in the Optical Burst Switching (OBS) network, the throughput of TCP connections degrade. On the other hand, High Speed TCP (HSTCP) was proposed as an alternative to the use of TCP in high bandwidth-delay product networks. HSTCP aggressively increases the congestion window used in TCP, when the available bandwidth is high and decreases the window cautiously in response to a congestion event. In this work, we make a thorough simulation study of HSTCP over OBS networks. While the earlier works in the literature used a linear chain of nodes as the network topology for the simulation, we use the popular 14-node NSFNET topology that represents an arbitrary mesh network in our study. We also study the performance of HSTCP over OBS for different bandwidths of access networks. We use two different cases for simulations where in the first HSTCP connections are routed on disjoint paths while in the second they contend for resources in the network links. These cases of simulations along with the mesh topology help us clearly distinguish between the congestion and contention losses in the OBS network and their effect on HSTCP throughput. For completeness of study, we also simulate TCP traffic over OBS networks in all these cases and compare its throughput with that of HSTCP. We observe that irrespective of the access network bandwidth and the burst loss rate in the network, HSTCP outperforms TCP in terms of the throughput and robustness against multiple burst losses up to the expected theoretical burst loss probability of 10 −3.

TCP performance evaluation over AODV and DSDV in RW and SN mobility models

This paper presents evaluation and comparison of the TCP performance in different mobile scenarios generated by Random Waypoint (RW) and Social Network (SN) mobility models. To our knowledge, TCP performance in SN mobility is discussed for the first time. The impact of AODV and DSDV routing protocols on the TCP goodput, delay and drop rate performance is also discussed. Extensive simulation results and analysis showed that TCP has better performance over AODV than over DSDV and has more stable performance in SN mobility than in RW mobility. We suggest using more mobility models, in particular, such as SN, in the evaluations of the transport layer or routing layer protocols because the mobility patterns have impacts on the protocol performance.