GFiber Wifi Data netdev1.1 Seville, Spain Feb 2016 - - PowerPoint PPT Presentation

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GFiber Wifi Data netdev1.1 Seville, Spain Feb 2016 - - PowerPoint PPT Presentation

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Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain) GFiber Wifi Data netdev1.1 Seville, Spain Feb 2016 apenwarr@google.com These are my personal opinions. They do not necessarily

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GFiber Wifi Data

netdev1.1 Seville, Spain Feb 2016 apenwarr@google.com

These are my personal opinions. They do not necessarily reflect the opinions of my employer. Not even a little.

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Who are we?

Source: pcmag.com article

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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  • Privacy policy:

○ https://fiber.google.com/legal/privacy.html

  • Data stored for a strictly limited time
  • Just wifi stats:

○ Don’t log content or Internet endpoints

  • MAC addrs are anonymized and IP addrs removed
  • Extremely strict access and aggregation controls

A note on anonymity

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Background spectrum analyzer

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Background spectrum analyzer

Open source: https://gfiber.googlesource. com/vendor/google/ platform/+/master/spectralanalyzer/

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Number of nearby visible access points

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Real-world device capabilities

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Distribution of RSSI samples for each TV box

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Comparing signal reception on AP submodels

red = Router #1 (3 dB better!) blue = Router #2

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Latency: isoping from GFiber android app

Open source: https://gfiber.googlesource.com/vendor/google/platform/+/master/cmds/isoping.c

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Latency: isoping from GFiber android app (zoomed)

Open source: https://gfiber.googlesource.com/vendor/google/platform/+/master/cmds/isoping.c

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Wifiblaster: real world wifi speeds (cdf)

Open source: https://gfiber.googlesource.com/vendor/google/platform/+/master/wifiblaster/ Lawyerized design doc: http://www.tdcommons.org/dpubs_series/127/

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Wifiblaster: single-family vs multi-dwelling

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Signal strength cdf, single-family vs multi-dwelling

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Speed vs signal, single-family vs multi-dwelling

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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RSSI vs Mbps (individual samples)

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Performance drop with more connected stations

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Wifi “taxonomy” breakdowns

Open source: https://gfiber.googlesource.com/vendor/google/platform/+/master/taxonomy/

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Real world wifi speeds: particular phone model

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Real world wifi: Chromecast (needs minstrel-blues?)

Minstrel-blues from Linux Plumbers Conf 2014: http://www.linuxplumbersconf.net/2014/ocw/proposals/2439

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Partial channel overlap in crowded environments

AP

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STA1 STA2

  • 30

STA2

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STA1 AP AP STA1 STA2

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STA2

  • 30

STA1 AP

  • 20
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  • 60
  • 80

Kitchen Bedroom 1 Bedroom 2 Kitchen Bedroom 1 Bedroom 2 Kitchen Bedroom 1 Bedroom 2 Kitchen Bedroom 1 Bedroom 2

  • 50
  • 70
  • 50
  • 70
  • 50
  • 70
  • 50
  • 50
  • 70
  • 40
  • 60
  • 80

Open source channel selection: https://gfiber.googlesource.com/vendor/google/platform/+/master/waveguide/

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Channel

  • verlap:

before & after

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Wifi speed prediction based on theory

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Wifi speed prediction based on typical values

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Bandsteering (2.4 vs 5 GHz)

Dual-band, non-Apple devices only

Bandsteering patches: https://gfiber.googlesource.com/vendor/opensource/hostap/+/master

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Future: bounciness analysis

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Future: passive latency measurement

  • Measure time delays:

○ SYN to SYN-ACK: Internet-facing RTT ○ SYN-ACK to ACK: wifi-facing RTT

  • Allows measuring success of fq_codel, per-station

queuing, etc.

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Future: measuring effects of airtime fairness

* Without airtime fairness, slow clients can ruin it for everyone. :(

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)

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Yakthulhu (and Questions?)

Proceedings of NetDev 1.1: The Technical Conference on Linux Networking (February 10th-12th 2016. Seville, Spain)