IEPM

PingER History Table Help

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There are two sets of PingER History tables.

FAQs

What do the metrics mean?
See the tutorial for definitions of Ping Loss (Packet Loss), Ping Response (Average Round Trip Time), Unpredictability, Unreachability, Zero Packet Loss Frequency, TCP Throughput, Conditional Loss Probability, Inter-packet-delay-Variability (IPDV), Out-of-order Packets. In future the value will be based on the degree of out-of-ordering, if someone cares to define it. Inter-Quartile Range (IQR) is the well-known statistics value for each sample (typically 10 pings). The reported value is the average of all the IQR's calculated in the time period of each tick covered by the report. Duplicate Packets . Again, sometime in the future the value will be based on the degree of duplication, if someone define it. Minimum Round Trip Time is simply the lowest round trip time observed during the tick. This indicates what the connection is capable of, and the difference between the minimum and the average indicates the load on the network. The minimum Round Trip Time can also be used to evaluate whether the link utilizes a geo-synchronous satellie, in which case the minimum RTT is likely to be over 500ms (lower limit on geosynchronous orbit is between 22,000 and 23,000 miles, speed of light is ~ 186,000 miles, figure up and back is 45,000, and round-trip is 90,000 miles, so we get 500ms right there). Minimum Packet Loss .
How is the row order chosen?
The row order in "Display Site to Site" is remote sites with the most monitoring sites are at the top.
Can I export this table to Excel?
The Site by Month table can be exported. The idea is that you select the group you want (this can be done directly in the Site vs. Month table or indirectly by clicking on the appropriate cell in the PingER history tables by Group) to get the appropriate Site vs. Month table. You will find a clickable link in the Site table, labelled something like "tab-separated-value (.tsv)". This will create a tab separated value file (e.g. pinghistory.tsv) which you can then save and later click on to launch Excel or assuming your browser platform is Excel capable, you can configure your browser to launch Excel directly (how to do this varies from browser to browser and release to release).
How do I export the table with the colors etc. so it is suitable for a presentation (this recipe comes from David Williams)?
How do I find out the full name of the monitoring or remote host in the Site by Month table?
Look at the columns on the far right.
Why does the report show a negative value for packet loss?
The reason for this is we sometimes see more packets received than sent, and rather than fudge it the report honestly reports the ping response.

Notes

Known Problems ...

No known problems at this time.

Added in release 2.0

Added in release 0.7 Added in release 0.5 Added in release 0.4. Added in release 0.3. Added in release 0.2. Back to top

Revised February 15, 2007
URL: http://www-iepm.slac.stanford.edu/pinger/table.html
Comments to iepm-l@slac.stanford.edu