Transcript Coordinating Cellular Background Transfers using

Abhijnan Chakraborty, Vishnu Navda, Venkataa N. Padmanabhan,
Ramachandran Ramjee
Microsoft Research India
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Presented by ZWZ.
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Introduction
Motivation
LoadSense
The Peak-n-Sneak Protocol
Evaluation
Discussion
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Background transfers.
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Fluctuant throughput.
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Cellular Workload.
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Is throughput stable?
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100G+ data download over 100+ hours.
Airtel: 3G and LTE in Bangalore, India
AT&T: LTE in Seattle, US
BSNL: 3G in Bangalore, India
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What if we can predict the throughput?
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Is signal quality (pilot power) a good indicator?
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The Metric: Power Radio
◦ PR = PilotPower/TotalRawPower
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Both link quality and cellular load have an
impact on the throughput.
Link quality
Cellular load
LTE
RSRP
RSRQ
3G
RSCP
ECIO
Obtaining these information using a Specified
tool from QualComm, QXDM, on a Windows
Phone.
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Predicting throughput.
◦ High (≥1.5Mbps) or low (<1.5Mbps).
◦ Using SVM (RBF)
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Peek: LoadSense.
Sneak: Collision resolution.
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Micro-benchmarks
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Macro-benchmarks
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Key point: throughput prediction with SVM.
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Contributions：
◦ LoadSense.
◦ Peek-n-Sneak protocol, which saves energy
consumption.
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Other factors?
◦ Pilot power & power ratio. Movement?
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Possible directions.
◦ Inference.
 Correlation estimation/prediction.
◦ Using SVM. (原因<=>结果)
 app能耗分析，对一些用量(内存、radio等)做SVM，然后可
以就可以通过这个来判定是否会引起battery drain.
 Diagnosis. 同样的套路。
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Q&A