NAT is accepted for transition purposes; for example NAT64 makes it trivial to connect from v6-only clients to v4 servers, and is used by some large ISPs (e.g.

NAT is accepted for transition purposes; for example NAT64 makes it trivial to connect from v6-only clients to v4 servers, and is used by some large ISPs (e.g. T-Mobile in the US) to avoid running v4 inside their access network.