Invited Talk: Hybrid Network Modeling and Simulation for Scale

Hybrid Network Modeling and Simulation for Scale (大规模网络混合建模与仿真技术)

2nd Global Future Network Development Summit
第二届全球未来网络发展峰会
Nanjing, China
May 11-12, 2018

Abstract

Modeling and simulation (M&S) plays an important role in the design analysis and performance evaluation of complex systems. Many of these systems, such as computer networks, involve a large number of interrelated components and processes. Complex behaviors emerge as these components and processes inter-operate across multiple scales at various granularities. M&S must be able to provide sufficiently accurate results while coping with the scale and complexity. This talk will focus on some novel techniques in high-performance network modeling and simulation. One is hybrid network traffic modeling, which can offload the computationally intensive bulk traffic calculations to the background onto GPU, while leaving detailed simulation of network transactions in the foreground on CPU. The other is distributed network emulation with simulation symbiosis, which uses an abstract network model to coordinate distributed emulation instances with superimposed traffic model to represent large-scale network scenarios.

中文摘要:建模与模拟(Modeling and Simulation, M&S)在复杂系统的设计分析与性能评估中发挥着重要作用。这些系统中的很多(如计算机网络)涉及大量相关的组件和流程。随着这些组件和流程在不同粒度的多个尺度上进行交互操作,复杂行为就会相应出现。 M&S必须能够在应对规模和复杂性的同时提供足够准确的结果。这次演讲将集中讨论高性能网络建模和模拟中的一些新技术。一种是混合网络流量建模,它可以将计算密集型的大量流量计算转移到GPU后台上,同时在CPU前台留下网络事务的详细模拟。另一种是采用与模拟协同的分布式网络仿真,它采用抽象网络模型、通过叠加的流量模型来协调分布式仿真实例,以表示大规模的网络场景。

SIMUTOOLS’17 Paper: Improving Real-Time SDN Simulation

On Improving Parallel Real-Time Network Simulation for Hybrid Experimentation of Software Defined Networks, Mohammad Abu Obaida and Jason Liu. In Proceedings of the 10th EAI International Conference on Simulation Tools and Techniques (SIMUTOOLS 2017), September 2017. [paper]

Abstract

Real-time network simulation enables simulation to operate in real time, and in doing so allows experiments with simulated, emulated, and real network components acting in concert to test novel network applications or protocols. Real-time simulation can also run in parallel for large-scale network scenarios, in which case network traffic is represented as simulation events passed as messages to remote simulation instances running on different machines. We note that substantial overhead exists in parallel real-time simulation to support synchronization and communication among distributed instances, which can significantly limit the performance and scalability of the hybrid approach. To overcome these challenges, we propose several techniques for improving the performance of parallel real-time simulation, by eliminating parallel synchronization and reducing communication overhead. Our experiments show that the proposed techniques can indeed improve the overall performance. In a use case, we demonstrate that our hybrid technique can be readily integrated for studies of software-defined networks.

Bibtex

@inproceedings{st17-realtime,
title = {On Improving Parallel Real-Time Network Simulation for Hybrid Experimentation of Software Defined Networks},
author = {Mohammad Abu Obaida and Jason Liu},
booktitle = {Proceedings of the 10th EAI International Conference on Simulation Tools and Techniques (SIMUTOOLS 2017)},
month = {September},
year = {2017}
}

Invited Talk: Faster and Better Hybrid Testbeds for Future Network Research

Faster and Better Hybrid Testbeds for Future Network Research

June 1, 2017

Future Network Theory and Application Laboratory (FNL)
Beijing University of Posts and Telecommunications, Beijing, China
Host: Professor Tao Huang (黄韬)

Abstract: Modeling and simulation (M&S) plays an important role in the design analysis and performance evaluation of computer networks. The ability to execute large-scale simulation on high-end computing systems has enabled us to model detailed and complex network behaviors. However, the difficulty in reproducing realistic large-scale network phenomena goes beyond designing efficient parallel algorithms. This talk will cover some of the recent high-performance network modeling and simulation techniques, particularly in the context of developing testbeds for future network research. We will focus specifically on our recent research in real-time simulation, hybrid network traffic modeling, and symbiotic simulation and emulation.

Invited Talk: High-Performance Modeling and Simulation of Computer Networks

High-Performance Modeling and Simulation of Computer Networks

May 26, 2017

Department of Computer Science
Tsinghua University, Beijing, China
Host: Professor Zhihui Du (都志辉)

Abstract: Modeling and simulation (M&S) plays an important role in the design analysis and performance evaluation of complex systems. Many of these systems, such as computer networks, involve a large number of interrelated components and processes. Complex behaviors emerge as these components and processes inter-operate across multiple scales at various granularities. M&S must be able to provide sufficiently accurate results while coping with the scale and complexity.

My talk will focus on two novel techniques in high-performance network modeling and simulation. The first is a GPU-assisted hybrid network traffic modeling method. The hybrid approach offloads the computationally intensive bulk traffic calculations to the background onto GPU, while leaving detailed simulation of network transactions in the foreground on CPU. Our experiments show that the CPU-GPU hybrid approach can achieve significant performance improvement over the CPU-only approach.

The second technique is a distributed network emulation method based on simulation symbiosis. Mininet is a container-based emulation environment that can study networks consisted of virtual hosts and OpenFlow-enabled virtual switches on Linux. It is well-known, however, that experiments using Mininet may lose fidelity for large-scale networks and heavy traffic load. The proposed symbiotic approach uses an abstract network model to coordinate distributed Mininet instances with superimposed traffic to represent large-scale network scenarios.

ICC’17 Paper: Mininet Symbiosis

Distributed Mininet with Symbiosis, Rong Rong and Jason Liu. In Proceedings of the IEEE International Conference on Communications (ICC 2017), May 2017.  [paper]

Abstract

Mininet is a container-based emulation environment that can study networks with virtual hosts and OpenFlow- enabled virtual switches on Linux. However, it is well-known that experiments using Mininet may lose fidelity for large- scale networks and heavy traffic load. One solution is to use a distributed setup where an experiment constitutes multiple instances of Mininet running on a cluster, each handling a subset of virtual hosts and switches. Such arrangement, however, is still constrained by bandwidth and latency limitations in the physical connection between the instances. In this paper, we propose a novel method of integrating distributed Mininet instances using a symbiotic approach, which extends an existing method for combining real-time simulation and emulation. We use an abstract network model to coordinate the distributed instances, which are superimposed to represent the target network. In this case, one can more effectively study the behavior of real imple- mentation of network applications on large-scale networks, since the interaction between the Mininet instances is only capturing the effect of contentions among network flows in shared queues, as opposed to having to exchange individual network packets, which can be limited by bandwidth or sensitive to latency. We provide a prototype implementation of the new approach and present validation studies to show it can achieve accurate results. We also present a case study that successfully replicates the behavior of a denial-of-service (DoS) attack protocol.

Bibtex

@INPROCEEDINGS{icc2017-symbiosis,
author={R. Rong and J. Liu},
booktitle={2017 IEEE International Conference on Communications (ICC)},
title={Distributed mininet with symbiosis},
pages={1-6},
doi={10.1109/ICC.2017.7996343},
month={May},
year={2017}
}

Slides

Invited Talk: High-Performance Modeling and Simulation of Computer Networks

High-Performance Modeling and Simulation of Computer Networks

April 26, 2017

Laboratory of Information, Networking and Communication Sciences (LINCS), Paris, France
Host: Professor Dario Rossi

Abstract: Modeling and simulation (M&S) plays an important role in the design analysis and performance evaluation of complex systems. Many of these systems, such as computer networks, involve a large number of interrelated components and processes. Complex behaviors emerge as these components and processes inter-operate across multiple scales at various granularities. M&S must be able to provide sufficiently accurate results while coping with the scale and complexity.
My talk will focus on two novel techniques in high-performance network modeling and simulation. The first is a GPU-assisted hybrid network traffic modeling method. The hybrid approach offloads the computationally intensive bulk traffic calculations to the background onto GPU, while leaving detailed simulation of network transactions in the foreground on CPU. Our experiments show that the CPU-GPU hybrid approach can achieve significant performance improvement over the CPU-only approach.
The second technique is a distributed network emulation method based on simulation symbiosis. Mininet is a container-based emulation environment that can study networks consisted of virtual hosts and OpenFlow-enabled virtual switches on Linux. It is well-known, however, that experiments using Mininet may lose fidelity for large-scale networks and heavy traffic load. The proposed symbiotic approach uses an abstract network model to coordinate distributed Mininet instances with superimposed traffic to represent large-scale network scenarios.

Invited Talk: Extending PrimoGENI for Symbiotic Distributed Network Emulation

Extending PrimoGENI for Symbiotic Distributed Network Emulation

March 13, 2017

GENI Regional Workshop (GRW), held in conjunction with GEC25 Miami, Florida, USA

The talk includes recent development in hybrid at-scale network experimentation, which extends the previous PrimoGENI project.

[slides]

Invited Talk: Symbiotic Modeling and High-Performance Simulation

Symbiotic Modeling and High-Performance Simulation

January 19, 2017

Department of Computer Science, Colorado School of Mines
Host: Professor Tracy Camp

Abstract: Modeling and simulation plays an important role in the design analysis and performance evaluation of complex systems. Many of these systems, such as the internet and high-performance computing systems, involve a huge number of interrelated components and processes. Complex behaviors emerge as these components and processes inter-operate across multiple scales at various granularities. Modeling and simulation must be able to provide sufficiently accurate results while coping with the scale and the complexity of these systems. My talk will focus on some of our latest advances in high-performance modeling and simulation techniques. I will focus on two specific case studies, one on network emulation and the other on high-performance computing (HPC) modeling.
In the first case, I will present a novel distributed network emulation mechanism based on modeling symbiosis. Mininet is a container-based emulation environment that can study networks consisted of virtual hosts and OpenFlow-enabled virtual switches on Linux. It is well-known, however, that experiments using Mininet may lose fidelity for large-scale networks and heavy traffic load. We propose a symbiotic approach, where an abstract network model is used to coordinate the distributed emulation instances superimposed to represent the target network. In doing so, we can effectively study the behavior of real implementation of network applications on large-scale networks in a distributed environment.
In the second case, I will present our latest work on performance modeling of HPC architectures and applications. In collaboration with the Los Alamos National Laboratory, we have developed a highly efficient simulator, called Performance Prediction Toolkit (PPT), which can facilitate rapid and accurate performance prediction of large-scale scientific applications on existing and future HPC architectures.

TOMACS’15 Paper: Symbiotic Network Simulation and Emulation

Symbiotic Network Simulation and Emulation, Miguel Erazo, Rong Rong, and Jason Liu. ACM Transactions on Modeling and Computer Simulation (TOMACS), 26(1), Article No. 2, December 2015. [paper]

abstractbibtex
A testbed capable of representing detailed operations of complex applications under diverse network conditions is invaluable for understanding the design and performance of new protocols and applications before their real deployment. We introduce a novel method that combines high-performance large-scale network simulation and high-fidelity network emulation, and thus enables real instances of network applications and protocols to run in real operating environments and be tested under simulated network settings. Using our approach, network simulation and emulation can form a symbiotic relationship, through which they are synchronized for an accurate representation of the network-scale traffic behavior. We introduce a model downscaling method along with an efficient queuing model and a traffic reproduction technique, which can significantly reduce the synchronization overhead and improve accuracy. We validate our approach with extensive experiments via simulation and with a real-system implementation. We also present a case study using our approach to evaluate a multipath data transport protocol.
@article{Erazo2015:symbiosis,
author = {Erazo, Miguel A. and Rong, Rong and Liu, Jason},
title = {Symbiotic Network Simulation and Emulation},
journal = {ACM Trans. Model. Comput. Simul.},
issue_date = {December 2015},
volume = {26},
number = {1},
month = jun,
year = {2015},
issn = {1049-3301},
pages = {2:1–2:25},
articleno = {2},
numpages = {25},
url = {http://doi.acm.org/10.1145/2717308},
doi = {10.1145/2717308},
acmid = {2717308},
publisher = {ACM},
address = {New York, NY, USA},
}

DSRT’15 Paper: Scalable Emulation with Simulation Symbiosis

Toward Scalable Emulation of Future Internet Applications with Simulation Symbiosis, Jason Liu, Cesar Marcondes, Musa Ahmed, and Rong Rong. In Proceedings of the 19th IEEE/ACM International Symposium on Distributed Simulation and Real Time Applications (DS-RT 2015), October 2015. [paper]

abstractbibtex
Mininet is a popular container-based emulation environment built on Linux for testing OpenFlow applications. Using Mininet, one can compose an experimental network using a set of virtual hosts and virtual switches with flexibility. However, it is well understood that Mininet can only provide a limited capacity, both for CPU and network I/O, due to its underlying physical constraints. We propose a method for combining simulation and emulation to improve the scalability of network experiments. This is achieved by applying the symbiotic approach to effectively integrate emulation and simulation for hybrid experimentation. In this case, one can use Mininet to directly run OpenFlow applications on the virtual machines and software switches, with network connectivity represented by detailed simulation at scale.
@INPROCEEDINGS{Liu2015:emulation-symbiosis,
author={J. Liu and C. Marcondes and M. Ahmed and R. Rong},
booktitle={Proccedings of the 2015 IEEE/ACM 19th International Symposium on Distributed Simulation and Real Time Applications (DS-RT)},
title={Toward Scalable Emulation of Future Internet Applications with Simulation Symbiosis},
year={2015},
pages={68-77},
doi={10.1109/DS-RT.2015.19},
ISSN={1550-6525},
month={Oct},
}