• Title/Summary/Keyword: TCP traffic

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ABR Service Control Algorithms For Improving Performance of TCP/IP: Simulation Evaluation (TCP/IP 성능개선을 위한 ABR 서비스 제어 알고리즘: 시뮬레이션 평가)

  • Park, Hui-Dae;Park, Seung-Seop
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.11S
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    • pp.3390-3398
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    • 1999
  • To achieve high-speed communication and to improve QoS characteristics, ATM is now being used as underlying transfer mechanism of Internet protocols, or TCP/IP. When TCP uses the ABR service in ATM networks, the ABR service control is important to improve the performance of TCP/IP traffic as long as there is no interaction between ABR rate control and TCP flow control. In such environment, the interoperability of EFCI and ER switches becomes unavoidable in order to more effectively control ABR traffic in ATM network. In this paper, we use the model of mixed EFCI-ER environment and discuss the performance issues, e.g., the fairness of bandwidth allocation, drop rate, throughput by using various ER switch algorithms. Among various ERSwitch algorithms, we present one algorithm that have a less network topology and allocate the fair share of VC bandwidth by simulation results.

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Internet Traffic Control Using Dynamic Neural Networks

  • Cho, Hyun-Cheol;Fadali, M. Sami;Lee, Kwon-Soon
    • Journal of Electrical Engineering and Technology
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    • v.3 no.2
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    • pp.285-291
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    • 2008
  • Active Queue Management(AQM) has been widely used for congestion avoidance in Transmission Control Protocol(TCP) networks. Although numerous AQM schemes have been proposed to regulate a queue size close to a reference level, most of them are incapable of adequately adapting to TCP network dynamics due to TCP's non-linearity and time-varying stochastic properties. To alleviate these problems, we introduce an AQM technique based on a dynamic neural network using the Back-Propagation(BP) algorithm. The dynamic neural network is designed to perform as a robust adaptive feedback controller for TCP dynamics after an adequate training period. We evaluate the performances of the proposed neural network AQM approach using simulation experiments. The proposed approach yields superior performance with faster transient time, larger throughput, and higher link utilization compared to two existing schemes: Random Early Detection(RED) and Proportional-Integral(PI)-based AQM. The neural AQM outperformed PI control and RED, especially in transient state and TCP dynamics variation.

Congestion Control with Multiple Time Scale under Self-Similar Traffic (자기유사성 트래픽 조건에서 다중 시간 간격을 이용한 혼잡제어)

  • Park, Dong-Suk;Ra, Sang-Dong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.1
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    • pp.65-75
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    • 2005
  • Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. We have advanced the framework of the multiple time scale congestion control and showed its effectiveness at enhancing performance for the rate-based feedback control. Our contribution is threefold. First, we define a modular extension of the TCP-a function called with a simple interface-that applies to various flavours of the TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

Design and Implementation of TCP Supporting Optional Encryption Functionalities (선택적인 암호화 기능을 지원하는 TCP의 설계 및 구현)

  • Seong, Jeong-Gi;Kim, Eun-Gi
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.1
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    • pp.190-195
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    • 2018
  • Recently, Due to the ongoing increase in cyber attacks and the improved awareness of privacy protection, most Internet services encrypt the traffic by using security protocols. Existing security protocols usually have additional layer between transport layer and application layer, and they incur additional costs because of encrypting all the traffic transmitted. This results in unnecessary performance degradation because it also encrypts data that does not require confidentiality. In this paper, we propose TCP OENC(Optional Encryption) which enables users of the application layer to optionally encrypt only confidential data. TCP OENC operates by TCP option to allow the application layer to encrypt the TCP stream transmitted only on demand. And it ensures transparency between the TCP layer and the application layer. To verify this, we verified that TCP OENC optionally encrypts the stream of TCP session on the embedded board. And then analyzed the performance of the encrypted stream by measuring the elapsed time.

Study on Self-similiarity of Aggregated TCP-IP Traffic (다중화된 TCP-IP 트래픽의 자기유사성에 관한 연구)

  • Cho, Hyeon-Seob;Jun, Ho-Ik
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.138-141
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    • 2010
  • Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

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An Efficient Buffer Management Scheme for TCP Traffic Transmission in ATM Networks (ATM망에서 TCP 트래픽 전송을 위한 효율적 버퍼관리 기법)

  • Kim, Byun-Gon;Kim, Nam-Hee
    • Journal of Korea Multimedia Society
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    • v.8 no.8
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    • pp.1099-1107
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    • 2005
  • The Guaranteed Frame Rate(GFR) service has been designed to accomodate non-real-time applications, such as TCP/IP based traffic in ATM networks. The GFR service not only guarantees a minimum throughput at the frame level, but also supports a fair share of available resources. In this paper, we propose a cell scheduling scheme which can improve the fairness and the goodput through the traffic control in GFR service. For the evaluation of the proposed scheme, we compare the proposed scheme with the existing scheme in the fairness and the goodput. Simulation results show that proposed scheme can improve the fairness and goodput comparing with the existing buffer management scheme.

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A Study about Web Traffic Performance on wired and wireless network (유무선 혼합망에서 웹 트래픽 성능에 관한 연구)

  • Kim, Chang Hee
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.7 no.2
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    • pp.47-58
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    • 2011
  • Snoop was suitably designed for wired and wireless network as having snoop agent module in BS(Base Station) which is connecting to both wired and wireless network in order to supplement the problems of TCP. This study examined performance difference by using the web traffic taken wide possession in current internet traffic. The web traffic has greater amount of traffic, shorter life time, and smaller size than other traffics. This study found that snoop producing performance improvement of wireless network in the network mixed with the wired and wireless lead performance loss when transmitting web traffic. This study found that in case of web traffic is transmitted it bring a performance improvement of web traffic as computing BWE((Bandwidth Expansion), and also found that this study prove of performance improvement by decreasing local retranmission.

Candidate Path Selection Method for TCP Performance Improvement in Fixed Robust Routing

  • Fukushima, Yukinobu;Matsumura, Takashi;Urushibara, Kazutaka;Yokohira, Tokumi
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.6
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    • pp.445-453
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    • 2016
  • Fixed robust routing is attracting attention as routing that achieves high robustness against changes in traffic patterns without conducting traffic measurement and performing dynamic route changes. Fixed robust routing minimizes the worst-case maximum link load by distributing traffic of every source-destination (s-d) router pair onto multiple candidate paths (multipath routing). Multipath routing, however, can result in performance degradation of Transmission Control Protocol (TCP) because of frequent out-of-order packet arrivals. In this paper, we first investigate the influence of multipath routing on TCP performance under fixed robust routing with a simulation using ns-2. The simulation results clarify that TCP throughput greatly degrades with multipath routing. We next propose a candidate path selection method to improve TCP throughput while suppressing the worst-case maximum link load to less than the allowed level under fixed robust routing. The method selects a single candidate path for each of a predetermined ratio of s-d router pairs in order to avoid TCP performance degradation, and it selects multiple candidate paths for each of the other router pairs in order to suppress the worst-case maximum link load. Numerical examples show that, provided the worst-case maximum link load is less than 1.0, our proposed method achieves about six times the TCP throughput as the original fixed robust routing.

A Study to Guarantee Minimum Bandwidth to TCP Traffic over ATM-GFR Service (ATM-GFR 서비스에서 TCP 트래픽의 최소 대역폭 보장에 관한 연구)

  • 박인용
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.4C
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    • pp.308-315
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    • 2002
  • Guaranteed frame rate (GFR) service has been defied to provide minimum cell rate (MCR) guarantees for virtual connections (VCs) carrying Internet traffic in ATM networks and allow them to fairly share residual bandwidth. The simplest switch implementation mechanism to support the GFR service in ATM networks consists of the frame-based generic cell rate algorithm (F-GCRA) frame classifier and the early packet discard (EPD)-like buffer acceptance algorithm in a single FIFO buffer. This mechanism is simple, but has foiled to guarantee the same bandwidth as an MCR to a VC that has reserved a relatively large MCR. This paper applies the packet spacing scheme to TCP traffic to alleviate its burstness, so as to guarantee a larger MCR to a VC. In addition, the random early detection (RED) scheme is added to the buffer acceptance algorithm in order to improve fairness in use of residual bandwidth. Simulation results show that the applied two schemes improve a quality of service (QoS) in the GFR service for the TCP traffic.

PAQM: an Adaptive and Proactive Queue Management for end-to-end TCP Congestion Control

  • Ryu Seung Wan
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.05a
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    • pp.417-424
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    • 2003
  • In this paper, we introduce and analyze a feedback control model of TCP/AQM dynamics. Then, we propose the Pro-active Queue Management (PAQM) mechanism, which can provide proactive congestion avoidance and control using an adaptive congestion indicator and a control function for wide range of traffic environments. The PAQM stabilizes the queue length around a desired level while giving smooth and low packet loss rates independent of the traffic load level under a wide range of traffic environment. The PAQM outperforms other AQM algorithms such as Random Early Detection (RED) [1] and PI-controller [2]

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