Not used in the sense you imagine, but I designed a hack where we hash IPv6 addresses into 224/3 (class D and E space) so backends that don't support IPv6 can still be provided a pseudo-IP. This accelerated support of IPv6 across all Google services without needing to wait for each individual backend to provide support. See https://www.nanog.org/meetings/nanog50/presentations/Wednesday/NANOG50.Talk4... slide 4 for a description, or http://docs.guava-libraries.googlecode.com/git/javadoc/com/google/common/net... for open-sourced code. There may be other uses for IPs beyond routing. Damian On Wed, Jun 17, 2015 at 2:07 PM, Luan Nguyen <lnguyen@opsource.net> wrote:
Is that safe to use internally? Anyone using it? Just for NATTING on Cisco gears...