<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><span style="caret-color: rgb(51, 51, 51); color: rgb(51, 51, 51); font-family: "Open Sans", Helvetica, Arial, sans-serif; font-size: 13px; background-color: rgb(252, 252, 252);" class="">2317 is actually 10 miles down the east lancs rd but configuration says manchester</span><div class=""><font color="#333333" face="Open Sans, Helvetica, Arial, sans-serif" size="2" class=""><span style="caret-color: rgb(51, 51, 51); background-color: rgb(252, 252, 252);" class=""><br class=""></span></font></div><div class=""><font color="#333333" face="Open Sans, Helvetica, Arial, sans-serif" size="2" class=""><span style="caret-color: rgb(51, 51, 51); background-color: rgb(252, 252, 252);" class="">Col</span></font></div><div class=""><font color="#333333" face="Open Sans, Helvetica, Arial, sans-serif" size="2" class=""><span style="caret-color: rgb(51, 51, 51); background-color: rgb(252, 252, 252);" class=""><br class=""></span></font><div><br class=""><blockquote type="cite" class=""><div class="">On 26 Mar 2021, at 06:25, Mccherry, Paul (Student) <<a href="mailto:p.mccherry@lancaster.ac.uk" class="">p.mccherry@lancaster.ac.uk</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">Thanks Robert</div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">I am using the probe estimated geolocations to validate a new active geolocation method I am formulating.</div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">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.</div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">However, I have other probes that have similar but different issues and whilst I am working my way through these issues a<span style="background-color: rgb(255, 255, 255); display: inline !important;" class="">ny additional information you can provide would be greatly appreciated. </span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class=""><br class=""></span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class="">Regards</span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class=""><br class=""></span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class=""><br class=""></span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class="">Paul McCherry</span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class="">Phd Student</span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><span style="background-color: rgb(255, 255, 255); display: inline !important;" class="">Lancaster University.</span></div><div style="caret-color: rgb(0, 0, 0); font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""> </div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><div id="appendonsend" class=""></div><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><hr tabindex="-1" style="display: inline-block; width: 454.71875px;" class=""><div id="divRplyFwdMsg" dir="ltr" class=""><font face="Calibri, sans-serif" style="font-size: 11pt;" class=""><b class="">From:</b><span class="Apple-converted-space"> </span>Robert Kisteleki <<a href="mailto:robert@ripe.net" class="">robert@ripe.net</a>><br class=""><b class="">Sent:</b><span class="Apple-converted-space"> </span>25 March 2021 12:47<br class=""><b class="">To:</b><span class="Apple-converted-space"> </span>Mccherry, Paul (Student) <<a href="mailto:p.mccherry@lancaster.ac.uk" class="">p.mccherry@lancaster.ac.uk</a>>;<span class="Apple-converted-space"> </span><a href="mailto:ripe-atlas@ripe.net" class="">ripe-atlas@ripe.net</a><span class="Apple-converted-space"> </span><<a href="mailto:ripe-atlas@ripe.net" class="">ripe-atlas@ripe.net</a>><br class=""><b class="">Subject:</b><span class="Apple-converted-space"> </span>[External] Re: [atlas] Probe location obfuscation</font><div class=""> </div></div><div class="BodyFragment"><font size="2" class=""><span style="font-size: 11pt;" class=""><div class="PlainText">This email originated outside the University. Check before clicking links or attachments.<br class=""><br class="">Hi,<br class=""><br class="">On 2021-03-25 13:00, Ponikierski, Grzegorz via ripe-atlas wrote:<br class="">> I would add to it additional problem that some hosts obfuscate probe<br class="">> location even more. For example you can find probes which in reality are<br class="">> located in US but are marked as CN or probes which are in reality in<br class="">> Wisconsin but are marked in California. Of course these are extreme<br class="">> cases. I guess most hosts just put a pin with probe location just<br class="">> somewhere around where it's locate as long it's in the same city. I<br class="">> don't remember, as a host of 3 probes, to get any precise<br class="">> recommendations how to mark probe location. Personally I just put a pin<br class="">> in city district where probe is locate.<br class=""><br class="">We don't have strict rules about precisely how the hosts should<br class="">geolocate their probes -- and could not enforce those even if we had<br class="">them. Instead we recommend doing this "roughly correct", which for some<br class="">hosts means city / neighbourhood is good enough, for some others it's<br class="">the exact spot of the utility box at home :-)<br class=""><br class="">> Can anyone confirm the geo-location obfuscation of probes as being up to<br class="">> 1km as per<br class="">><span class="Apple-converted-space"> </span><a href="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" class="">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</a><<a href="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" class="">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</a>><br class="">><br class="">> I am a Phd student carrying out research on the RIPE atlas platform and<br class="">> an early result seems to indicate 1 probe has an obfuscation of 10km<br class="">> distance but this may be an anomaly or perhaps something not taken into<br class="">> account as yet.<br class=""><br class="">We have a very simple algorithm that does the obfuscation consistently<br class="">with a certain maximum distance added, which may not be precisely 1km.<br class="">We can talk offline about the details if you're really interested in the<br class="">precise method.<br class=""><br class="">Cheers,<br class="">Robert</div></span></font></div></div></div></blockquote></div><br class=""></div></body></html>