So you have an application. It was written (as far as you know) without IPv6 in mind, and now it has to work with IPv6. How hard is that going to be? Well, it depends on the application. Most of the following is not really Java specific (but some of it is).
ULA (Unique Local Addresses, or Unique Local IPv6 Unicast Addresses to give them their full name) are IPv6’s equivalent of IPv4’s “private” addresses. The idea is to append a random 40 bits to the reserved ULA prefix fd00::/8, thus building a /48 that you can call your own. You can use this /48 wherever and however you like, with the sole proviso that it must not be routed on the … Continue reading
Why Not NAT? NAT came into existence because of IPv4 address scarcity. With IPv6, that reason disappears. So, if we no longer need to multiplex addresses, should we retain NAT?