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PingER (Ping End-to-end Reporting) is the name given to the Internet End-to-end Performance Measurement (IEPM) project to monitor end-to-end performance of Internet links. It is led by SLAC and development includes NUST/SEECS (formerly NIIT), FNAL, and ICTP/Trieste, together with UM,UNIMAS and UTM in Malaysia. Originally, in 1995 it was for the High Energy Physics community, however, this century it has been more focused on measuring the Digital Divide from an Internet Performance viewpoint. The project now involves measurements to over 700 sites in over 160 countries, and we are actively seeking new sites to monitor and monitoring sites for this project, as well as people interested in our data. It uses the ubiquitous ping facility so no special software has to be installed on the targets.

Measurements are made by ~60 measurement Agents (MAs) in 23 countries. They make measurements to over 700 targets in ~ 160 countries containing more than 99% of the world's connected population. The measurement cycle is scheduled at roughly 30 minute intervals. At each measurement cycle, each MA issues a set of pings to each target, stopping when it receives 10 ping responses or it has issued 30 ping requests. From each  set of pings one can derive various metrics such as minimum (Min) ping Round Trip Time (RTT) response, average (Avg) RTT, maximum (Max)  RTT, standard deviation (Stdev) of RTTs, 25% probability of RTT, 75% probability of RTT, Inter Quartile Range (IQR, )loss, reachability (host is unreachable if get 100 % loss).

The data is publicly available and since the online data goes back to January 1998, it provides 19 years of historical data.

Raspberry Pi Model and Specifications

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Both were in the same building at SLAC, i.e. roughly at latitude 37.4190 N, longitude 122.2085 W. The machines are about 30 metres apart or about 0.0003 msec based on the speed of light in fibre. 

The measurements were made between pinger.slac.stanford.edu and pinger-raspberry.slac.stanford.edu and from both pinger.slac.stanford.edu and  pinger-raspberry.slac.stanford.edu to targets at varying distances and hence varying minimum RTTs from SLAC. The Directivity in the table provide a measure of how direct the route is between the MA and target. The Directivity is given as:
 Directivity = great circle distance between MA & target [in km] / (RTT [ms] * 100 [km/ms]

The Directivity is <=  of 1, and a value of 1 means the RTT is the same as given by the speed of light in a fibre. 

49.2475 N 

123.2308 W

46.23 N

6.07 E

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