Why do we still need IPv4 when we are migrating to IPv6...

[Erik Kline]

> From our perspective, doing investments on CGN/AFTR technology now can almost be comparable with buying address, as we must consider deprecation on the equipment anyways. If we can wait a bit longer and the IPv4 traffic lowers to for example 10% and then do the CGN /AFTER investment, it would possibly be cheaper and possibly be done with equipment we already have. I guess seen from a pure economics perspective it does not make much difference, but at least we can uphold the native IPv4 until the majority of ISP's and content providers are fully Dual-Stacked.

What does "IPv4 traffic lowers to...10%" mean here?

Is this 10% meant to suggest that you'll wait until 90% of the
Internet has IPv6, or when the average dualstack user's traffic mix
will reach 90% IPv6 to 10% IPv4?