It would be nice if we could implement a way to allow only inbound email from specific countries.
For example:
I have a USA based company that expects to only recieve email from other American companies. Taking that as a given assumption I could go into the interface and 'uncheck' all countries but the USA for inbound mail. On the back end this would compare all inbound connections to a definition-updated list, and if it does not match one of the allowed ranges the connection would be refused.
Currently each country has a set of IP ranges that are easily identifiable and available from ICANN. With the current issue of Snowshoe Spam and reputation based filtering this would provide our customers with another effective way to limit inbound spam as much of it originates overseas. Think of how much spam could be blocked if you only accepted emails from one Nation. If we make this a component of the UI it could be easily modified to allow emails from additional countries as the business expands internationally. Alternatively if you find your environment is recieving a massive amount of spam from one country you could easily go in and refuse all email from that point of origin until the spam campaign ends.