I had fun making it but please note that the current implementation is just a demo and far from a proper production tool.
If you really want to use it then for best possible results you need at least 500 probes per phase.
It could be optimized fairly easily but not without going over the anon user limit which I tried to avoid
Start by doing the multi-continent probe, say 3x each. Drop the longest time probes, add probes near the shortest time, and probe once. Repeat this pattern of probe, assess, drop and add closer to the target.
You accumulate all data in your orchestrator, so in theory you don't need to deliberately issue multiple probes each round (except for the first) to get statistical power. I would expect this to "chase" the real location continuously instead of 5 discrete phases.
I just watched the Veritasium video on potentials and vector fields - the latency is a scalar potential field of sorts, and you could use it to derive a latency gradient.
Internet signals generally travel by cable, and the selected route may or may not be the shortest distance.
It's quite possible for traffic between neighboring countries to transit through another continent, sometimes two. And asymetric routing is also common.
Since this is using traceroute anyway, if you characterize the source nodes, you could probably use a lot fewer nodes and get similar results with something like:
a) probe from a few nodes on different continents (aiming to catch anycast nodes)
b) assuming the end of the trace is similar from all probes, choose probe nodes that are on similar networks, and some other nodes that are geolocated nearby those nodes.
c) declare the target is closest to the node with the lowest measured latency (after offsetting from node charachterized first hop latency)
You'll usually get the lowest ping times if you can ping from nearby customer of the same ISP as the target. Narrowing to that faster is possible if you know about your nodes.
Plenty of developers really like it too though, because that's where Claude learned to use it.
You could do even cooler tricks, like https://github.com/blechschmidt/fakeroute
Pointless? Almost certainly.
Oversubscription is expected to a certain degree (this is fundamentally the same concept as "statistical multiplexing"). But even oversubscription in itself is not guaranteed to result in bufferbloat -- appropriate traffic shaping (especially to "encourage" congestion control algorithms to back off sooner) can mitigate a lot of those issues. And, it can be hard to differentiate between bufferbloat at the last mile vs within the ISP's backbone.
Aha, that's what you would think, but what if I fake the source of the IP used to do the geolocation ping instead!
This brute force approach works much better than I expected as long as you have enough probes and a bit of luck.
But of course there are much better and smarter approaches to this, no doubt!
You mention the quality several times in the article but it's not clear how this is verified. Do you have a set of known-location-ip-addresses around the world (apart from your home)? Or are we just assuming that latency is a good indicator?
I tested against them, as well as other infrastructure I control that is not part of the network, and compared to the ipinfo results as well
However, ipinfo still appears to rely on active probing to triangulate geolocation data, which suggests they believe these routing asymmetries can be modeled or averaged out in practice.
The telco DSL and fiber in my metro area all runs through a single location where the PPPoE (hiss) concentrator is and the first hop latency from DSL interleaving swamps the latency from distance. You can someone is in the metro area, but not the county or city.
Cable company customers are a little more locatable, probably get the county.
so theres funky overlap wherein on one isp you appear closer to city A, and on isp 2 closer to city B, but its same physical address.
Continental classification I'd think would be good as they appear to be coalesced endpoints, separated by vast oceans.
struct tcp_info info;
socklen_t len = sizeof(info);
getsockopt(sock, IPPROTO_TCP, TCP_INFO, &info, &len);
How's this different from RIPE ATLAS?
Globalping offers real-time result streaming and a simpler user experience with focus on integrations https://globalping.io/integrations
For example you can use the CLI as if you were running a traceroute locally, without even having to register.
And if you need more credits you can simply donate via GitHub Sponsors starting from $1
They are similar with an overlapping audience yet have different goals
Sometimes residential ISPs (that hosts the probe) may have a bad routing due to many factors, how does the algorithm take that into account?
IEEE 802.11mc > Wi-Fi Round Trip Time (RTT) https://en.wikipedia.org/wiki/IEEE_802.11mc#Wi-Fi_Round_Trip...
/? fine time measurement FTM: https://www.google.com/search?q=fine+time+measurement+FTM
Seems tool is relying on ICMP results from various probes. So wouldn't this project become useless if target device disables ICMP?
I wonder if you can "fake" results by having your gateway/device respond with fake ICMP requests.
Email me if you would like to get some additional credits to test it out, dakulovgr gmail.