Abstract— Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. In this paper, we present analysis of hours of endto-end unicast and... more
Abstract— Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. In this paper, we present analysis of hours of endto-end unicast and multicast packet loss measurement. From these we selected,hours of stationary traces for further analysis. We consider the dependence as seen in the autocorrelation function of the original loss data as well as the dependence between good run lengths and loss run lengths. The correlation timescale is found to be,or less. We evaluate the accuracy of three models of increasing complexity: the Bernoulli model, the 2-state Markov chain model and the -th order Markov chain model. Out of the trace segments considered, the Bernoulli model was found to be accurate for segments, the 2-state model was found to be accurate for,segments. A Markov chain model of order,or greater was found to be necessary to accurately model the rest of the segments. For the case of adaptive applications which track loss, we address two issues of on-line loss estimation: the required memory,size and whether to use exponential smoothing or a sliding window average to estimate average loss rate. We find that a large memory,size is necessary and that the slidi ng window average provides a more accurate estimate for the same effective memory size.
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Abstract With the rapid growth of data centers, minimizing the queueing delay at network switches has been one of the key challenges. In this work, we analyze the shortcomings of the current TCP algorithm when used in data center... more
Abstract With the rapid growth of data centers, minimizing the queueing delay at network switches has been one of the key challenges. In this work, we analyze the shortcomings of the current TCP algorithm when used in data center networks, and we propose to use latency-based congestion detection and rate-based transfer to achieve ultra-low queueing delay in data centers.
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ABSTRACT We present PacketShader, a high-performance software router frame-work for general packet processing with Graphics Processing Unit (GPU) acceleration. PacketShader exploits the massively-parallel processing power of GPU to... more
ABSTRACT We present PacketShader, a high-performance software router frame-work for general packet processing with Graphics Processing Unit (GPU) acceleration. PacketShader exploits the massively-parallel processing power of GPU to address the CPU bottleneck in current ...
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Social networking services are a fast-growing business in the Internet. However, it is unknown if online relationships and their growth patterns are the same as in real-life social net- works. In this paper, we compare the structures of... more
Social networking services are a fast-growing business in the Internet. However, it is unknown if online relationships and their growth patterns are the same as in real-life social net- works. In this paper, we compare the structures of three online social networking services: Cyworld, MySpace, and orkut, each with more than 10 million users, respectively. We have access to complete
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Secure end-to-end communication is becoming increas- ingly important as more private and sensitive data is transferred on the Internet. Unfortunately, today's SSL deployment is largely limited to security or privacy- critical domains.... more
Secure end-to-end communication is becoming increas- ingly important as more private and sensitive data is transferred on the Internet. Unfortunately, today's SSL deployment is largely limited to security or privacy- critical domains. The low adoption rate is mainly at- tributed to the heavy cryptographic computation over- head on the server side, and the cost of good privacy on the Internet
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Routing loops are caused by inconsistencies in routing state among a set of routers. They occur in perfectly engineered networks, and have a detrimental effect on performance. They impact end-to-end performance through increased packet... more
Routing loops are caused by inconsistencies in routing state among a set of routers. They occur in perfectly engineered networks, and have a detrimental effect on performance. They impact end-to-end performance through increased packet loss and delay for packets caught in the loop, and through increased link utilization and corresponding delay and jitter for packets that traverse the link but
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Page 1. Synchronized Two-Way Voice Simulation Tool for Internet Phone Performance Analysis and Evaluation I Adrian E. Conway Racal-Datacom, 1601 North Harrison Parkway, Sunrise, FL 33323, USA Sue B. Moon Department ...
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Page 1. On the Design and Performance of Prefix-Preserving IP Traffic Trace Anonymization Jun Xu Jinliang Fan Mostafa Ammar Sue B. Moon College of Computing Sprint ATL Georgia Institute of Technology 1 Adrian Court Atlanta, GA 30332-0280... more
Page 1. On the Design and Performance of Prefix-Preserving IP Traffic Trace Anonymization Jun Xu Jinliang Fan Mostafa Ammar Sue B. Moon College of Computing Sprint ATL Georgia Institute of Technology 1 Adrian Court Atlanta, GA 30332-0280 Burlingame, CA 94010 ...
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ABSTRACT Effective data management has become a key in promoting data sharing within measurement-based research commu-nity. In this work we propose a framework that helps us to share not only the data, but also the data management... more
ABSTRACT Effective data management has become a key in promoting data sharing within measurement-based research commu-nity. In this work we propose a framework that helps us to share not only the data, but also the data management platform in order to promote ...
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ABSTRACT Twitter offers an explicit mechanism to facilitate information diffu-sion and has emerged as a new medium for communication. Many approaches to find influentials have been proposed, but they do not consider the temporal order of... more
ABSTRACT Twitter offers an explicit mechanism to facilitate information diffu-sion and has emerged as a new medium for communication. Many approaches to find influentials have been proposed, but they do not consider the temporal order of information adoption. In this ...
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ABSTRACT Twitter, a microblogging service less than three years old, com-mands more than 41 million users as of July 2009 and is growing fast. Twitter users tweet about any topic within the 140-character limit and follow others to receive... more
ABSTRACT Twitter, a microblogging service less than three years old, com-mands more than 41 million users as of July 2009 and is growing fast. Twitter users tweet about any topic within the 140-character limit and follow others to receive their tweets. The goal of this paper is ...
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ABSTRACT In this paper, we study the process of information diffusion in a microblog service developing Galton-Watson with Killing (GWK) model. Microblog services offer a unique approach to online information sharing allowing microblog... more
ABSTRACT In this paper, we study the process of information diffusion in a microblog service developing Galton-Watson with Killing (GWK) model. Microblog services offer a unique approach to online information sharing allowing microblog users to forward messages to others. We describe an information propagation as a discrete GWK process based on Galton-Watson model which models the evolution of family names. Our model explains the interaction between the topology of the social graph and the intrinsic interest of the message. We validate our model on dataset collected from Sina Weibo and Twitter microblog. Sina Weibo is a Chinese microblog web service which reached over 100 million users as for January 2011. Our Sina Weibo dataset contains over 261 thousand tweets which have retweets and 2 million retweets from 500 thousand users. Twitter dataset contains over 1.1 million tweets which have retweets and 3.3 million retweets from 4.3 million users. The results of the validation show that our proposed GWK model fits the information diffusion of microblog service very well in terms of the number of message receivers. We show that our model can be used in generating tweets load and also analyze the relationships between parameters of our model and popularity of the diffused information. To the best of our knowledge, this paper is the first to give a systemic and comprehensive analysis for the information diffusion on microblog services, to be used in tweets-like load generators while still guaranteeing popularity distribution characteristics.
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Abstract Commodity-hardware technology has advanced in great leaps in terms of CPU, memory, and I/O bus speeds. Benefiting from the hardware innovation, recent software routers on commodity PC now report about 10 Gbps in packet routing.... more
Abstract Commodity-hardware technology has advanced in great leaps in terms of CPU, memory, and I/O bus speeds. Benefiting from the hardware innovation, recent software routers on commodity PC now report about 10 Gbps in packet routing. In this paper we map out expected hurdles and projected speed-ups to reach 100 Gbps in packet routing on a single commodity PC. With careful measurements, we identify two notable bottlenecks for our goal: CPU cycles and I/O bandwidth. For the former, we propose reducing per-packet ...
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Internet speed at the edge is increasing fast with the spread of fiber-based broadband technology. The appearance of bandwidth-consuming applications, such as peer-to-peer file sharing and video streaming, has made traffic growth a... more
Internet speed at the edge is increasing fast with the spread of fiber-based broadband technology. The appearance of bandwidth-consuming applications, such as peer-to-peer file sharing and video streaming, has made traffic growth a serious concern like never before. Network operators fear congestion at their links and try to keep them underutilized while no concrete report exists about performance degradation at
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ABSTRACT Transmission control protocol (TCP) has been the dominating proto-col for Internet traffic for the past decades. Most network research based on traffic analysis (e.g., router buffer sizing and traffic classification) has been... more
ABSTRACT Transmission control protocol (TCP) has been the dominating proto-col for Internet traffic for the past decades. Most network research based on traffic analysis (e.g., router buffer sizing and traffic classification) has been conducted assuming the dominance of TCP over other protocols. However, a few recent traffic statistics are showing a sign of significant UDP traffic growth at various points of Internet links [21]. In this paper we show that the UDP traffic has grown significantly in recent years on our campus network; we have observed a 46-fold increase in volume (from 0.47% to 22.0% of total bytes) in the past four years. The trace collected in 2011 shows that the grown volume is not from a small number of UDP hosts nor port numbers. In addition, the recent UDP flows are not sent at constant bit rate (CBR) for most cases, and the aggregated traffic shows burstiness close to TCP traffic.
Abstract Many measurement systems have been proposed in recent years to shed light on the internal performance of the Internet. Their common goal is to allow distributed applications to improve end-user experience. A common hurdle they... more
Abstract Many measurement systems have been proposed in recent years to shed light on the internal performance of the Internet. Their common goal is to allow distributed applications to improve end-user experience. A common hurdle they face is the need to deploy yet another measurement infrastructure. In this work, we demonstrate that without any new measurement infrastructure or active probing we obtain composite performance estimates from AS-by-AS segments and the estimates are as good as (or even better than) ...
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We present MBone experiments that validate an end-to-end measurement technique we call Multicast Inference of Network Characteristics (MINC). MINC exploits the performance correlation experienced by multicast receivers to infer loss rates... more
We present MBone experiments that validate an end-to-end measurement technique we call Multicast Inference of Network Characteristics (MINC). MINC exploits the performance correlation experienced by multicast receivers to infer loss rates and other attributes of internal links in a multicast tree. MINC has two important advantages in the Internet context: it does not rely on network collaboration and it scales
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ABSTRACT We present PacketShader, a high-performance software router frame-work for general packet processing with Graphics Processing Unit (GPU) acceleration. PacketShader exploits the massively-parallel processing power of GPU to... more
ABSTRACT We present PacketShader, a high-performance software router frame-work for general packet processing with Graphics Processing Unit (GPU) acceleration. PacketShader exploits the massively-parallel processing power of GPU to address the CPU bottleneck in current ...
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The online relationship in Twitter, known as follow, is directed. People can follow any other person without an approval. In this article we show novel aspects of Twitter that come from the directionality in relationships: topological... more
The online relationship in Twitter, known as follow, is directed. People can follow any other person without an approval. In this article we show novel aspects of Twitter that come from the directionality in relationships: topological characteristics of the directed network, word-of-mouth information spreading via retweet, and online relationship dissolution. We wrap up the article with future directions in our
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Inconsistencies in routing state cause routing loops in the In- ternet. A routing loop causes packets trapped in the loop to be delayed or discarded, depending on whether or not the packet exits the loop. Internet routing protocols... more
Inconsistencies in routing state cause routing loops in the In- ternet. A routing loop causes packets trapped in the loop to be delayed or discarded, depending on whether or not the packet exits the loop. Internet routing protocols aggregate routable ad- dresses into prefixes, and so many packets can be caught in a loop involving a given prefix, allowing routing loops to impact a substantial quantity of traffic. We present a new method for detecting routing loops from packet traces, and apply our method to a selection of packet traces taken from Sprint's IP backbone. Routing loops cause packets caught in the loop to traverse the same link in the network multiple times, and to show up as replicas of the original packet in the trace. We term a set of replicas with a suitably decrementing TTL (Time-To-Live) a replica stream and identify replica streams in the traces. As one routing loop may cause many packets to be replicated, we then merge replica streams caused by the same routi...
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We propose a general framework which can be used for modeling and predicting the popularity of online contents. The aim of our modeling is not inferring the precise popularity value of a content, but inferring the likelihood with which... more
We propose a general framework which can be used for modeling and predicting the popularity of online contents. The aim of our modeling is not inferring the precise popularity value of a content, but inferring the likelihood with which the content will be popular. Our ...
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Page 1. Multimedia Systems (1998) 6:1728 Multimedia Systems c Springer-Verlag 1998 Packet audio playout delay adjustment: performance bounds and algorithms Sue B. Moon, Jim Kurose, Don Towsley Department of Computer ...
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Abstract— Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. In this paper, we present analysis of hours of endto-end unicast and... more
Abstract— Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. In this paper, we present analysis of hours of endto-end unicast and multicast packet loss measurement. From these we selected,hours of stationary traces for further analysis. We consider the dependence as seen in the autocorrelation function of the original loss data as well as the dependence between good run lengths and loss run lengths. The correlation timescale is found to be,or less. We evaluate the accuracy of three models of increasing complexity: the Bernoulli model, the 2-state Markov chain model and the -th order Markov chain model. Out of the trace segments considered, the Bernoulli model was found to be accurate for segments, the 2-state model was found to be accurate for,segments. A Markov chain model of order,or greater was found to be necessary to accurately model the rest of the segments. For the case of adap...
Research Interests:
Research topics that can benefit from packet-level monitoring are: Developing traffic models that allow network operators to determine the amount of overprovisioning required in their network [3] Assessing the trade-offs between... more
Research topics that can benefit from packet-level monitoring are: Developing traffic models that allow network operators to determine the amount of overprovisioning required in their network [3] Assessing the trade-offs between different levels of granu-larity in routing, and ...
Research Interests: Distributed Computing, Network Management, System Design, Network, File Sharing, and 10 moreInternet and Media Streaming, TCP performance, Size Distribution, Passive Acoustic Monitoring, Storage Area Network, Speed of Light, Round Trip Time, Electrical And Electronic Engineering, Network Traffic Measurement, and Internet traffic
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Research Interests: Distributed Computing, Software Engineering, Queueing theory, Network Flows, Internet Measurement, and 12 moreTomography, Statistical Inference, Network Performance, Maximum Likelihood Estimation, Network Architecture, Network Topology, Simulation experiment, IEEE Communications Magazine, Software Tool, Statistical Estimation, Internet, and Electrical And Electronic Engineering
AbstractUser generated content (UGC), now with millions of video producers and consumers, is re-shaping the way people watch video and TV. In particular, UGC sites are creating new viewing patterns and social interactions, empowering... more
AbstractUser generated content (UGC), now with millions of video producers and consumers, is re-shaping the way people watch video and TV. In particular, UGC sites are creating new viewing patterns and social interactions, empowering users to be more creative, and ...
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Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. We present analysis of 128 hours of end-to-end unicast and multicast packet loss... more
Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. We present analysis of 128 hours of end-to-end unicast and multicast packet loss measurement. From these we selected 76 hours of stationary traces for further analysis. We consider the dependence as seen in the autocorrelation function of the original loss