Coordinating Cellular Background Transfers

using LoadSenseAbhijnan Chakraborty, Vishnu Navda, Venkataa N. Padmanabhan,

Ramachandran RamjeeMicrosoft Research India

.Presented by ZWZ.

Introduction Motivation LoadSense The Peak-n-Sneak Protocol Evaluation Discussion

Outline

Background transfers.

Fluctuant throughput.

Cellular Workload.

Introduction

Is throughput stable?◦ 100G+ data download over 100+ hours.◦ Airtel: 3G and LTE in Bangalore, India◦ AT&T: LTE in Seattle, US◦ BSNL: 3G in Bangalore, India

Motivation

What if we can predict the throughput?

Is signal quality (pilot power) a good indicator?

Motivation

The Metric: Power Radio◦ PR = PilotPower/TotalRawPower

LoadSense

Both link quality and cellular load have an impact on the throughput.

Obtaining these information using a Specified tool from QualComm, QXDM, on a Windows Phone.

LoadSense

Link quality Cellular load

LTE RSRP RSRQ

3G RSCP ECIO

Predicting throughput.◦ High (≥1.5Mbps) or low (<1.5Mbps).◦ Using SVM (RBF)

LoadSense

Peek: LoadSense. Sneak: Collision resolution.

Peek-n-Sneak Design

Micro-benchmarks

Evaluation

Macro-benchmarks

Evaluation

Key point: throughput prediction with SVM.

Contributions：◦ LoadSense.◦ Peek-n-Sneak protocol, which saves energy

consumption.

Conclusion

Other factors?◦ Pilot power & power ratio. Movement?

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。

Discussion

S

A B C

Thanks!Q & A