Anycast Resolution in OONI measurements
Currently, OONI measurements are not anycast aware. When a domain resolves to an IP which is served by multiple servers depending on geographic location, we have no way to determine which actual server the client attempts to contact, or where it is.
This is a broad issue, and there are several smaller components that need to be addressed to do a reasonable job of resolution. First, we need to know which IPs are anycasting, then we need to know the locations of the different servers, and finally we need to know which clients are routed to which servers.