My thoughts of this made the parallelism with IP addresses. Japan's issue can be solved by "buying some numbers" from much smaller countries. The solution to r

My thoughts of this made the parallelism with IP addresses. Japan's issue can be solved by "buying some numbers" from much smaller countries. The solution to reuse a number is bat shit crazy. Perhaps they can use expired cards (and not cancelled). In the long run the sensible solution (just like IP addresses) is to move from a "IPv4" system to a "IPv6" that will largely multiply the available numbers per country/bank/entity and will solve the problems, for the next many decades.