Howdy sir! Great memory and fun times :)

Dataset was something from CAIDA, like this: https://www.caida.org/catalog/datasets/ipv4_prefix_probing_d...

IIRC we used the LGL algorithm (https://lgl.sourceforge.net/) while pinning any nodes we could get geolocations for, giving a nice hybrid geo/topo layout

I don't remember exactly how we got the geolocations, but often network routers have 3-letter airport codes in their DNS names, so maybe that? We may also have had a lookup table in el googz somewhere

Definitely a project whose time should again come! ;)