Network Address Translation
Why: Internet commercialization (early 1990s)
Predicted shortage of official IP-adresses
Long term solution: IPv6 (128 bit addresses)
Shorter term solutions: translation logic (RFC 1631, 1994) and private (non routable) addresses (RFC 1918, 1996)
When official addresses are not
available
practical
Our IPv6 code originally came from the KAME project