Date near end of line is last tested date. Each one has a link to a network information tool, which will do an nslookup, visual ping, 30-packet ping, or traceroute to it. A tableless version is also available. SMTP query, nslookup. The backbone network is BBNPlanet.
Docs are available here .
RFC 1393 deals with the Internet pseudo-standard for traceroute. Some English documentation can be found here , here , or here . David Dennis's 'Club Traceroute' list of web traceroute gateways. Laurent Demailly's list . Page from Isoft with cached traces to sites in Switzerland and around the world.