Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Obs: Make sure to change the default password for Raspbian.

Measurements

We chose to make detailed measurements from two monitors at SLAC.

  1. The Dell Poweredge 2650 bare metal pinger.slac.stanford.edu server running Red Hat Linux  2.6.32-504.8.1.el6.i686
  2. The Raspberry Pi pinger-raspberry.slac..stanford.edu an armv61 running Gnu Linux.

Both were in the same building at SLAC.

Analysis

Looking for significant differences in the measurements of  the more important metrics (average, median and jitter of RTT and loss) that impact applications such as throughput, voice over IP, streaming video, haptics.  

The jitter is represented by the Inter packet Delay (IPD).

Example target = pinger.unimas.my (~220 msec.)

...

For 100Byte the round trip time series for RTTs did not have similar behaviour. We noticed a great change mainly in the maximum round trip time. The average em minimum RTT did not change that much. Another point about pinger-raspberry is that it increases significantly the  RTT for near nodes (about ~1ms). The difference is greater than if we compare a node which is in a long distance.

...

To sitka.triumf.ca from SLAC

...

 

 pinger.slac.stanford.edu to sitka.triumf.capinger-raspberry.slac.stanford.edu to sitka.triumf.ca
Time Series
Frequency distribution RTT
Frequency distribution Abs(IPD)
Frequency distribution IPD

...