A IPv6 only host has to have access to a IPv4 address to talk to IPv4 only
hosts. The simplest way to do this is to actually stay dual stack and use
... the simplest (and recommended) way to do this is to use dual stack
(full stop). DS-Lite is needed in some situations, primarily if you want
to enable a v6-only ISP network and want to share one IPv4 address among
multiple subscribers. But regular dual stack works very well, too, and
is often deployed in the NATted-IPv4 and routed IPv6 configuration.
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