[arin-ppml] Why are ISPs allowed?

[michael.dillon at bt.com]

> Is there a reason why ISP's such as Comcast/ATT, allowed to 
> hand out unique IP addresses, even not static ones, to end 
> users? Why are they not required to use NAT?
> 
> If ISPs were to switch to local address space, how many IP 
> blocks would be released back into the wild?

A few years ago, Comcast noted that there was not enough
addresses in the RFC 1918 space for them to fully number
their network, therefore, they began the move to using
IPv6 internally. There is a pointer on this page
<http://www.getipv6.info/index.php/IPv6_Presentations_and_Documents>
to a Comcast presentation about how and why.


--Michael Dillon