Morning Raaarty..............how's the chooks?...[for those in far off distant lands.......'how's the chooks' is just an OZ colloquial term for "how are you going mate?"]

Many people confuse IP as 'insulation protection' when it is actually ''International Protection [IP] Ratings"
But typical of the Americans,....no they were not satisfied with an International code, so they established their own

......accordingly we see IP68 = the American NEMA code of 6P
You will see that the IP Coding table is a simple visual/text combination to determine the requirements, however NEMA is simply a table which must be referenced to another text table to understand what it means

Having said this I am sure you are correct about IP addresses & they are unique to each & every computer in the world.......so there must be lots of them

With model ships & electricals & water

, safest bet is to try & maintain IP67 or IP68 for everything possible .................. Derek