Once we have the codes and DB schema for storing IP WHOIS information (see subtask T174553), it is time for WMF to decide where to obtain this data, when to obtain this data (on demand, or in batch) and how often to update the data.
Sources mentioned so far are MaxMind (http://maxmind.github.io/GeoIP2-php/) and IPInfo (http://ipinfo.io/about). It has been mentioned that the MaxMind data may be in accurate in that it assumes all IPv4's have a /24 subnet (which is often wrong); on the other hand, IPInfo seems not to allow "batch" downloads (it only allows on demand queries, IIRC).
Another issue to discuss is pricing and licensing. If a paid data source is eventually selected as the most appropriate solution, WMF has to agree to pay for it.