Hacker News new | past | comments | ask | show | jobs | submit login
How to Catch When Proxies Lie [pdf] (cmu.edu)
62 points by jsnell 4 months ago | hide | past | web | favorite | 3 comments

A very thorough and relevant piece of network measurement work! Awesome.

An interesting result not related to the title is some scary disagreements between popular geoip databases and the active probes the authors used(§6.2):

> All five of the IP-to-location databases are more likely to agree with the providers’ claims than either active-geolocation approach is. As discussed earlier, we are inclined to suspect that this is because the proxy providers have influenced the information in these databases. We have no hard evidence backing this suspicion, but we observe that there is no pattern to the countries for which the IP-to-location databases disagree with provider claims. This is what we would expect to see if the databases were being influenced, but with some lag-time.

The paper does call out the geoip databases in question (DB-IP, Eureka, IP2Location, IPInfo, MaxMind) -- but not the VPN providers, which is unfortunate.

Also, the code looks quite good: https://github.com/zackw/active-geolocator

They missed one which is used by lots of ad networks including Google and Facebook: digital element's ip location DB.

Why Google and Facebook will need external vendor for geo IP DB? They have GPS data (or location based on WiFi / Cellular triangulation if GPS is switched off) and can name own geo IP DB. Given number of users this DB will be more accurate than most other vendors can provide.

Applications are open for YC Summer 2019

Guidelines | FAQ | Support | API | Security | Lists | Bookmarklet | Legal | Apply to YC | Contact