Use of unique local IPv6 addressing rfc4193

Karl Auer kauer at
Fri Sep 9 00:49:34 UTC 2016

On Thu, 2016-09-08 at 23:43 +0000, Pshem Kowalczyk wrote:
> both ways - if we decide to use it we'll have to either overlay it
> with public IPv6 space (and provide the NAT/proxy for where we don't
> have any public IPv6 assigned) or simply not use the fc00::/7 and
> skip the NAT/proxy aspects of it.

There is no necessary link between ULA addresses and NAT. You don't
have to NAT ULA, *ever*. If you need public addresses, go get them.
There are enough.

IMHO one should use ULA in only three situations:

- a completely isolated network
- for internal communications e.g. fabric management)
- for testing

Regards, K.

Karl Auer (kauer at

GPG fingerprint: E00D 64ED 9C6A 8605 21E0 0ED0 EE64 2BEE CBCB C38B
Old fingerprint: 3C41 82BE A9E7 99A1 B931 5AE7 7638 0147 2C3C 2AC4

More information about the NANOG mailing list