As a security measure, we block all incoming traffic from outside of the US to reduce any attempts of DDoS attacks or scrapers trying to steal data from us. This system has worked very well for us as it provides a base standard for security. We can then further analyze access log in greater detail.
A good number of people have mentioned that they were seeing 403 errors when browsing our maps, even though they are physically located in the US. Doing some research shows that their IPs are indeed located in the US. One thing, that every person who reported seeing these 403 errors, have in common is their ISP – Frontier Communications.
Doing even more research, apparently this company has bought Verizon’s customers in a number of states, including Texas and Florida! For some strange reason, all of the IPs assigned to their customers somehow have a geolocation from Canada. Because of this, all users who have Frontier Communications as their ISP were getting blocked erroneously.
Now that we know the cause, we have allowed traffic coming in from Canada and those of you that were seeing these errors before should no longer see them.
If you still see 403 errors, please contact us at firstname.lastname@example.org and let us know your IP address you are connecting from.