IETF: IPv6 No Longer Optional!
Snippet from RFC6540 IPv6 Support Required for All IP-Capable Nodes:

To ensure interoperability and flexibility, the best practices are as

o New IP implementations must support IPv6.

o Updates to current IP implementations should support IPv6.

o IPv6 support must be equivalent or better in quality and
functionality when compared to IPv4 support in a new or updated IP

o New and updated IP networking implementations should support IPv4
and IPv6 coexistence (dual-stack), but must not require IPv4 for
proper and complete function.

o Implementers are encouraged to update existing hardware and
software to enable IPv6 wherever technically feasible.

This Best Current Practice RFC is directed both at vendors of network equipment (routers/switches/firewalls/etc) and end-station equipment.

#IPv6 now, people!

Via +Asbjørn Højmark
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