[Jory]

Hello. I have a Huawei GPON from my ISP, he is connected to some PC's and to a router with Wifi. Once when I called ISP customer support they was able to tell devices connected to GPON.
I want to use dd-wrt to have more privacy, how should I do this ? I should change the GPON ? or I should disconnect all devices from GPON and let only router connected to GPON, use a DD-WRT firmware for router and connect other PC's only from router ? Or I need to turn off some GPON settings ? What I should do ?

[tedm]

You need to start by learning what you have and proper terminology. Here is a diagram of a typical GPON network:

http://gponsolution.com/gpon-technology-diagram.html

You likely have an ONT in your home. But until you can confirm what you have we don't know anything because it would be like your saying "can I replace my fiber with dd-wrt" it is meaningless.

If your setup IS like the diagram then are you saying that your ONT is a combined ONT device + wifi router? Or is it an ONT and a separate wifi router? If it is a combined ONT and wifi router then no, you can't replace it. You MIGHT be able to have the ISP reconfigure the ONT as a "dumb bridge" and plug a wifi router into it that is running dd-wrt.

The problem you have is you don't know how this network is setup. The GPON could for example be completely privately numbered and there is actually no router at all. It could be that there's a router in your house that is VPNing your connectivity to the ISP. There's a million ways to set all this stuff up and some aren't compatible with running your own router.

Contact your ISP and tell them you need a single public IP address in your home and you are going to assign that to your router and handle your internal network. It can be statically or dynamically assigned. See if they can supply that or not. If they can't then you cannot run your own router. Instead you will need to run a bridged firewall solution such as the free Untangle firewall from untangle.com

[Jory]