Conference Papers
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506
Browse
7 results
Search Results
Item Performance evaluation of TCP variants over routing protocols in multi-hop wireless networks(2010) Tahiliani, M.P.; Shet, K.C.; Basavaraju, T.G.Wireless internet has become popular in recent years due to the tremendous growth in the number of mobile computing devices and high demand for continuous network connectivity regardless of physical locations. In this paper, we investigate the effects of routing protocols on the performance of Transmission Control Protocol (TCP) variants in multi-hop wireless networks. Through simulations we study the effects of Destination Sequenced Distance Vector (DSDV), Optimized Link State Routing (OLSR), Ad hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) routing protocols on TCP Tahoe, TCP Reno, TCP Newreno, TCP with Selective Acknowledgment (SACK) option and TCP Vegas. The simulations are carried out for static as well as mobile nodes. The performance metric used is throughput. Another metric, expected throughput is used for the comparison of throughput when nodes are mobile. ©2010 IEEE.Item Experimental analysis of CUBIC TCP in error prone MANETs(IEEE Computer Society help@computer.org, 2014) Kumari, D.; Tahiliani, M.P.; Shenoy, U.K.K.CUBIC TCP, a variant of the traditional TCP, is the default congestion control algorithm deployed in Linux kernels above 2.6 version. CUBIC is mainly designed for high speed, long distance wired networks and several studies have exhibited that it indeed, enriches the performance of such networks. Recently, hand-held devices such as smart phones have grown very popular and there has been a lot of interest in the research community to design efficient operating systems for such devices. Android is one of the latest open source mobile operating system and it is based on a reduced version of the Linux kernel. Since it is Linux based, CUBIC TCP remains the default TCP in Android also. These hand-held devices, however, are connected to low speed wireless networks and consequently, CUBIC TCP deployment in Android ends up being a mismatch. The main goal of this work is to analyze the behavior of CUBIC TCP in low speed error prone wireless networks and bring out the challenges and issues related to the same. © 2014 IEEE.Item CSS: Cautious Slow Start algorithm to minimize packet drop rate(Institute of Electrical and Electronics Engineers Inc., 2017) Swapna, C.; Tahiliani, M.P.Slow Start algorithm helps the TCP flows to quickly ramp up their congestion window (cwnd) by employing an exponential increase pattern. This pattern of increasing cwnd leads to consecutive loss of packets in bulk, and hence, results in large number of packets being re-transmitted. Recently, the limitations of this approach have become apparent as many Internet applications are becoming more sensitive to packet loss and latency. In this paper, we propose a Cautious Slow Start (CSS) algorithm which aims to mitigate the bulk packet losses that occur with the traditional Slow Start algorithm. This is achieved by increasing the cwnd cautiously, instead of doubling it. We validate the effectiveness of CSS algorithm by simulating a variety of Internet like scenarios in ns-2, and comparing its performance with that of the traditional Slow Start algorithm. CSS algorithm successfully mitigates the bulk packet losses, without affecting the overall link and buffer utilization. © 2016 IEEE.Item Proportional rate reduction for ns-3 TCP(Association for Computing Machinery acmhelp@acm.org, 2018) Mittal, V.; Jain, V.; Tahiliani, M.P.The implementation of Transmission Control Protocol (TCP) in the Linux kernel has kept pace with its ongoing research. However, it is not the case with the implementations of TCP in network simulators. This limitation has been a major hindrance in thoroughly evaluating the performance of new TCP extensions, since carrying out real-time experimental evaluations is a non-trivial task. Recently, there have been significant efforts to align the TCP implementation in ns-3 to that of Linux. Nonetheless, there still exist several features that the implementation of TCP in ns-3 lacks. In this work, the TCP implementation in ns-3 has been extended to support Proportional Rate Reduction (PRR) algorithm. PRR is a de facto loss recovery algorithm used since Linux kernel 3.2. This paper describes the implementation and validation of PRR algorithm in ns-3 and also highlights the need to modularize the implementation of loss recovery algorithms in ns-3. © 2018 Copyright held by the owner/author(s).Item Design and implementation of TCP BBR in ns-3(Association for Computing Machinery acmhelp@acm.org, 2018) Jain, V.; Mittal, V.; Tahiliani, M.P.Bottleneck Bandwidth and Round-trip propagation time (BBR) is a congestion based congestion control algorithm recently proposed by Google. Although it can be deployed with any transport protocol that supports data delivery acknowledgement, BBR is presently implemented alongside TCP (known as TCP BBR) in Linux kernel since 4.9 and is the default congestion control used in Google Cloud Platform. However, to the best of our knowledge, TCP BBR is not yet supported in popular network simulators such as ns-3. This limitation is a major hindrance in thoroughly studying the benefits of TCP BBR since carrying out large-scale and real-time experimental evaluations is a non-trivial task. In this paper, we discuss the design and implementation of a new model for TCP BBR in ns-3. We validate the proposed model by performing different sets of simulations to ensure that the model in ns-3 exhibits key characteristics of TCP BBR. © 2018 Copyright held by the owner/author(s).Item Recent acknowledgement support for ns-3 TCP(Association for Computing Machinery, 2019) Bakshi, S.; Tahiliani, M.P.Recent Acknowledgement (RACK) is a TCP packet loss detection technique proposed by Google. It uses the notion of time to detect packet losses instead of packet or sequence counting approaches like Fast Retransmit and other non-standard techniques. RACK algorithm is described in an Internet Draft in the TCP Maintenance Working Group (tcpm) at IETF and is the de facto loss detection technique since Linux 4.4. However, to the best of our knowledge, there does not exist a model to study RACK using network simulators. Network simulations provide flexibility to extensively evaluate the upcoming network protocols without resorting to complex real-time experiments. In this paper, we propose the design, implementation and validation of a new model for RACK in ns-3. We evaluate RACK by comparing its performance with Fast Retransmit and verify that the model in ns-3 exhibits key attributes of RACK. © 2019 ACM.Item Linux-like Loss Detection Techniques for ns-3 TCP(Institute of Electrical and Electronics Engineers Inc., 2019) Bakshi, S.; Sahoo, A.P.; Keerthana, P.; Bhalekar, D.; Tahiliani, M.P.Recent Acknowledgment (RACK) is a new loss detection technique for TCP proposed by Google and described in an Internet Draft in TCP Maintenance Working Group (tcpm) of IETF. It is the default loss detection technique in Linux kernel. RACK internally uses Forward Acknowledgement (FACK) and Duplicate Selective Acknowledgement (DSACK) loss detection techniques, and leverages the benefits of Tail Loss Probe (TLP). This paper describes the implementation and evaluation of FACK, DSACK and TLP loss detection techniques for TCP model in ns-3. The goal is to provision prerequisite loss detection techniques in ns-3 for implementing RACK. The implementation of FACK, DSACK and TLP in Linux is used as a reference for this work. Our implementation of these techniques in ns-3 is verified by evaluating their performance in respective scenarios and ensuring that they exhibit their key characteristics. © 2019 IEEE.