from realworld experience in providing IPv6 services at an ISP,
and as a customer of that service:
/48 PA assignments to the customer is sufficient.
for roaming clients (like travelling laptops with PPP) there's a
IMHO even a traveling laptop with PPP needs to be able to subnet.
I've lost count of the number of times I've needed to do this in IPv4
but been stuck with a single /32. I have also lost count of the number
of times I've used a laptop as a router in the days when I had a /28
routed to me. Built in NAT capability for IPv4 that allows a single PPP
connection to be shared over wireless seems fairly common these days.
We need the equivalent capability in IPv6, just without NAT.
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