TULIP landmarks are servers at well kown locations (lat/longs), that can ping a requested target (typically at an unknown location) to use geolocation to find the location of the target. There are several sources of potential TULIP landmarks. These include PingER, perfSONAR and PlanetLabs. The current list of TULIP landmarks can be found by looking at the list.
If you need to verify the location (latitude/longitude) of a landmark then see TULIP Landmark finding the latitude longitude manually.
perfSONAR
Use the perfSONAR list of traceroute/ping servers. It is at: http://132.160.6.186/toolkit/gui/perfAdmin/directory.cgi#PING. This provide a list of IP names/address that host traceroute/ping servers. Then add to the perfSONAR toolkit host name (e.g. 192.41.236.35 or 2001:e10:3c00:3:5054:ff:fe12:ee41) the following
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One could search for the string (for example <td>Latitude,Longitude</td><td>-41.28131,174.77575</td>) and extract the lat/long. A script could be written to automate this using wget to get the web pages etc.
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