On Tue, 20 Apr 2004, Iljitsch van Beijnum wrote: > It seems that there are now organizations who want/need more private > address space than is available as per RFC 1918. Using class E space > for this would make a lot of sense as this allows for a lot of private > space without sacrificing usable unicast space. Can you elaborate? I used to work for Hitachi, which is/was then the 7th largest company in the world. I can think of very few organizations that need more than 1 /8 and 17 /16's of unique, non-public space. Allowing a non-global address space as a subset of the global space means that one (or many) can reach the public network through a default route that leads to a NAT. But if you have such a large network that it has something greater than 20 million hosts that must each have direct access to any of the rest, and you can't NAT internally, then you probably have reached a point where you will need a more sophisticated mechanism than NAT to reach the public internet. Underlying this is the question of whether such a large network really needs to simultanously reach the public network. If it doesn't, then there is no reason to limit oneself to the RFC 1918 space. I might also suggest that such a heavy address user migrate to IPv6 internally as IPv6 has similar problems and it is developing means to deal with them. --Dean _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf