On 9/28/20 6:16 PM, John Levine wrote:
You appear to be saying there will be mail systems that need to send
mail to IPv4 systems, but will not have an IPv4 mail server so the
recipients can't reply to them. Really?
No, I'm saying that when IPv4 starts going away, there will be more and
more systems needing to send mail via NAT to such that client and server
ends of the connection have different address types.
(There are already some IPv6 only ISPs and I expect this will become
more viable over time. Should they have to set up IPv4 tunnels or ALGs
for their "legitimate" customers so those customers can still send email
to IPv4 servers?)
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