Thanks Robert I am using the probe estimated geolocations to validate a new active geolocation method I am formulating.
The probe I that I thought had an anomaly was in fact found to be within 1k distance of my estimated geo location using the new method. The original discrepancy was due to a number of factors that I had failed to accurately apply. However, I have other probes that have similar but different issues and whilst I am working my way through these issues any additional information you can provide would be greatly appreciated. Regards Paul McCherry Phd Student Lancaster University. ________________________________ From: Robert Kisteleki <rob...@ripe.net> Sent: 25 March 2021 12:47 To: Mccherry, Paul (Student) <p.mcche...@lancaster.ac.uk>; ripe-atlas@ripe.net <ripe-atlas@ripe.net> Subject: [External] Re: [atlas] Probe location obfuscation This email originated outside the University. Check before clicking links or attachments. Hi, On 2021-03-25 13:00, Ponikierski, Grzegorz via ripe-atlas wrote: > I would add to it additional problem that some hosts obfuscate probe > location even more. For example you can find probes which in reality are > located in US but are marked as CN or probes which are in reality in > Wisconsin but are marked in California. Of course these are extreme > cases. I guess most hosts just put a pin with probe location just > somewhere around where it's locate as long it's in the same city. I > don't remember, as a host of 3 probes, to get any precise > recommendations how to mark probe location. Personally I just put a pin > in city district where probe is locate. We don't have strict rules about precisely how the hosts should geolocate their probes -- and could not enforce those even if we had them. Instead we recommend doing this "roughly correct", which for some hosts means city / neighbourhood is good enough, for some others it's the exact spot of the utility box at home :-) > Can anyone confirm the geo-location obfuscation of probes as being up to > 1km as per > https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fatlas.ripe.net%2Fabout%2Ffaq%2F%23are-the-locations-of-probes-made-public&data=04%7C01%7Cp.mccherry%40lancaster.ac.uk%7C0d707df0f3534cd8707008d8ef8c2bb3%7C9c9bcd11977a4e9ca9a0bc734090164a%7C0%7C1%7C637522732594157947%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=ZRNBZBO61oUXTYZGVYNyfyNRG2J4sv4AIrchzrCitOg%3D&reserved=0 > > <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Furldefense.com%2Fv3%2F__https%3A%2Fatlas.ripe.net%2Fabout%2Ffaq%2F*are-the-locations-of-probes-made-public__%3BIw!!GjvTz_vk!EWq0OCOmS-1Af9zWmGzygQZxC02O19msR11hqwe7X3bHqvxoqX8Tt17N3fDKNB4%24&data=04%7C01%7Cp.mccherry%40lancaster.ac.uk%7C0d707df0f3534cd8707008d8ef8c2bb3%7C9c9bcd11977a4e9ca9a0bc734090164a%7C0%7C1%7C637522732594157947%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=VdT77jYEFo5pWuPHqRjnowZPIq9neOLHKc%2B47slBNI8%3D&reserved=0> > > I am a Phd student carrying out research on the RIPE atlas platform and > an early result seems to indicate 1 probe has an obfuscation of 10km > distance but this may be an anomaly or perhaps something not taken into > account as yet. We have a very simple algorithm that does the obfuscation consistently with a certain maximum distance added, which may not be precisely 1km. We can talk offline about the details if you're really interested in the precise method. Cheers, Robert
