Date: Mon, 30 Jan 1995 16:15:23 -0800 From: postel@ISI.EDU (Jon Postel) This seems brain dead. I think the intent of 1597 was to say here are some numbers you can go play with privately. Since they are private they should never appear on the public Internet, anywhere, ever. Actually, the conclusion that I would draw from this (and that others have certainly drawn) is that RFC 1597 is brain dead. I'd certainly recommend that anyone who was contemplating numbering their network *not* use one of the 1597 numbers, and if their network provider tries to force them to do this "in order to save address space", to go find another network provider. As you've pointed out, by using the 1597 numbers, you're guaranteeing that that you can never use those numbers on the public Internet, and you'll never be able to use more than one network provider. Even if most of a companies hosts are behind a firewall, they'd still be better off using globally unique numbers. After all, if we all do our jobs right, maybe someday we can make the firewalls go away.... - Ted