> By definition NAT will maintain state which is translation table. Stateless NAT is also possible, but then it has to be 1:1. Which has it's purpose, but is r

> By definition NAT will maintain state which is translation table. Stateless NAT is also possible, but then it has to be 1:1. Which has it's purpose, but is rarely used. A practical example would be with IPv6 if your ISP doesn't allocate you a static prefix. Stateless NAT would allow you to use a /64 from the private range of fd00::/8 in your local network which the router would translate to your globally unique /64. No state needed, because there would be as many IPs available in your LAN prefix as in your GUA prefix. All it would do would be translating fdxx:xxxx:xxxx:xxxx:1234:1234:1234:1234 to 2yyy:yyyy:yyyy:yyyy:1234:1234:1234:1234 and vice versa. I've also done stateless NAT on IPv4. When you request more IPs from some cloud providers, they assign you a bunch of /32s, not a proper subnet, virtually requiring you to run a cloud router.