I changed the subject line.
At 11:41 25-09-2011, Keith Moore wrote:
My assumption is that most ISPs are already using RFC 1918 for
internal infrastructure whenever possible in order to free up more
public IPv4 addresses to assign to customers.
See draft-kirkham-private-ip-sp-cores-06 There is also 7/8 which was
used internally by an ISP . Some may use RFC 1918 addresses for
economic reasons  or because of its security properties. The
choice made by the ISP might be based on the notion of satisficing.
RFC 1287 argued for a plan which takes us past the exhaustion of the
(IPv4) address space. In my opinion, such a plan is unfeasible for
non-technical reasons. On a tangent, I don't know whether that RFC
contains the original S.I.N.
1. The market for lemons.
2. See Purchasing power parity. The discussion would be way
off-topic. RFC 1744 examined some of the issues associated with the
current management practices of the Internet IPv4 address space.
P.S. Although the subject line has been changed, it is not the
appropriate way to create a new thread as the subject line is not a
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