Edgebased Network Modeling and Inference

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Edge-basedNetwork Modelingand Inference
Vinay Ribeiro, Rolf Riedi, Richard Baraniuk
Rice University spin.rice.edu
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INCITE Project
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Available Bandwidth Estimation

• Available bandwidth unused bandwidth on path
• Key metric for data-intensive applications
• Estimate ABW by e2e active probing

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pathChirp Tool

• Based on principle of self-induced congestion
• Exponentially spaced chirp probe trains

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Internet Experiments

• 3 common hops between SLAC?Rice and Chicago?Rice
  paths

• Estimates fall in proportion to introduced
  Poisson traffic

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pathChirp Summary

• Balances probing uncertainty principle
• Efficient
• performs comparably to state-of-the-art tools
• (PathLoad, PacketPair, TOPP) using about 10x
  fewer packets
• Robust to bursty traffic
• incorporates multiscale statistical analysis
• Open-source software available at spin.rice.edu
• See poster Tuesday night

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AlphaBeta Model

• Causes of burstiness in network
  traffic(non-Gaussianity)?

beta
alpha
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AlphaBeta Model

• Causes of burstiness in network
  traffic(non-Gaussianity)?

beta
alpha
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Traffic Bursts A Case Study
Typical non-spiky epoch
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Traffic Bursts A Case Study
Typical spiky epoch
Typical non-spiky epoch
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Beta Alpha

• Bottlenecked elsewhere
• Large RTT

• Bottlenecked at this point
• Large file small RTT

fractional Gaussian noise
stable Levy noise
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spin.rice.edudsp.rice.edu
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CAIDA Gigabit Testbed

• Smartbit cross-traffic generator
• Estimates track changes in available bandwidth
• Performance improves with increasing packet size

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Grid Computing

• Harness global resources to improve performance

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Application Predict Download Time

• Dynamically schedule tasks based on bandwidth
  availability

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Optimal Path Selection

• Choose path to minimize download time from A to D

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Active Probing for Bandwidth

• Iperf, Pathload, TOPP,
• Self-induced congestion principleincrease
  probing rate until queuing delay increases
• Goal Minimally intrusive
• Lightweight probing with as few packets as
  possible

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Chirp Probing

• Chirp exponential flight pattern of probes
• Non-intrusive and Efficient wide range of
  probing bit rates, few packets

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Comparison with Pathload

• Rice ECE network
• 100Mbps links
• pathChirp can use 10x fewer bytes for comparable
  accuracy

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Conclusions

• pathChirp non-intrusive available bandwidth
  probing tool
• Successful tests on the Internet and Gigabit
  testbed
• Upto 10x improvement over state-of-the-art
  pathload on Rice ECE network
• Whats next?