It should be noted that this is a map at what we would call layer 3 in the OSI model. ipv4/ipv6 space and BGP relationships between ASes.
Giant transit ISPs like Cogent own little if any underlying fiber infrastructure, which is much harder to map and have 100% topology discovery of by researchers sitting at desks somewhere. Lots of transit ISPs like HE, Telia or Cogent buy inter-city transport from "carrier of carrier" specialists who own the underlying assets, run DWDM systems on them, and so forth.
Without proprietary information from carriers' GIS systems (at Level3/Lumen/Centurylink, Zayo or similar) it's much harder to do that.
What are they providing if they don't own the cables? Are they shared with other non-ISP issues, or is it more like when a company builds an office building and then leases it from themselves?
what I described above would be at layers 1 and 2 in the OSI model (the cable itself and underlying physical assets)
a company like Cogent, HE, they're providing at layer 3 the routers, network engineering, IP space (in many cases, not all, mostly for enterprise customers), and what is known as "IP transit" - transiting a customer's traffic through their network to all of their peers. And maintaining the cost of buying all those inter-city transport circuits to link all of their routers within their AS together.
Giant transit ISPs like Cogent own little if any underlying fiber infrastructure, which is much harder to map and have 100% topology discovery of by researchers sitting at desks somewhere. Lots of transit ISPs like HE, Telia or Cogent buy inter-city transport from "carrier of carrier" specialists who own the underlying assets, run DWDM systems on them, and so forth.
Without proprietary information from carriers' GIS systems (at Level3/Lumen/Centurylink, Zayo or similar) it's much harder to do that.