I recently changed from an ADSL 10 MB to a GPON 40 MB and since then I'm having a bad headache.
My old ISP (ADSL) gave me always a valid public IPv4. Sometimes it changed but there was no problem since I used dynamic dns to reassign my hostname and access my home Open VPN installed in a Raspberry Pi. That was sweet.
But now, my actual ISP (GPON) uses something I never heard of: my public IP is this 138.36.33.141 and according to their technical support, this same IPv4 address is used by more than one customer.
They installed a "Zhone ZNID-GPON-2426A-EU: S3.1.229" as the "router" for the fiber connection at my home. I tried to create DMZ and Port Forward (Remap) rules and they didn't worked so far...
Then... they told me that this public IPv4 address encapsulates (or sort of) my IPv6. They already enabled IPv6 with Prefix Delegation and IPv6 DHCP Server in the "router" (I really don't know if it is because it have a lot of functions). I can access my Raspberry Pi from outside with its IPv6 address (and tested VPN and SSH port in IPv6 online scanner page with positive results) but no no IPv4 access is possible (no Port Forward, no DMZ).
Since the place I work does not support IPv6 (just IPv4) is there something I can do to access my Home VPN through IPv4? It is possible using 6in4?