FiOS systems can have TWO MoCA networks on the coax. One for the LAN and one for the WAN. Verizon routers actually have two MoCA interfaces for each of these networks. These networks operate at different frequencies and may have different encryption keys.
MoCA WAN is used between the ONT and the router. The ONT creates the MoCA WAN network. As far as I know, the only devices that can connect to the ONT's MoCA WAN connections are Verizon routers. There used to be a MoCA WAN adaptor one could buy, but it has long since been discontinued. IF you can find it online, it will cost hundreds of dollars; no, I do not know the part number.
MoCA LAN is used between the router and client devices including set-top-boxes. The router creates the MoCA LAN network. The readily available MoCA adaptors are designed to work with this network, not the MoCA WAN.
Some people have used MoCA LAN adapters to create their own coax link between an ONT and their router. This works if you can install a MoCA adaptor next to the ONT and another next to the router. No other adapters can be used, as this is the WAN link and can only go to the router.
If you can figure out how to run Ethernet, you'll need to contact Verizon to switch the ONT from MoCA to Ethernet. If you find the right person it takes about five minutes for them to re-provision the ONT.
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