1. A method for determining a derived geographic location of a target Internet host, the method including: identifying a plurality of landmark Internet hosts communicatively coupled with each other and with the target Internet host by a packet-switched network; measuring first network latencies of first probe packets transmitted to the target Internet host and to each of the plurality of landmark Internet hosts along different network pathways in the network; calculating relative distances between the target Internet host and one or more of the landmark Internet hosts based on the first network latencies; comparing the relative distances to identify at least one of the landmark Internet hosts that is geographically closer to the target Internet host than one or more other landmark Internet hosts; and determining the derived geographic location of the target Internet host based on a geographic location of the at least one of the landmark Internet hosts that is geographically closer to the target Internet host.