Hi,
I couldn’t find any official confirmation of IPoE support, but it seems to be a term that ISPs use differently so, in my opinion, it's a bit misleading to focus on that.
In the case of "Japanese IPoE," which seems to be the topic here, it’s most likely about DS-Lite (Dual-Stack Lite) which is widely adopted in Japan. It is a method for transitioning networks to IPv6 while still supporting IPv4. Router needs to encapsulate IPv4 packets inside IPv6 packets and send them through an IPv6 tunnel. Since this process requires specific support for DS-Lite, you’d need an ISP-provided router to make it work.
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