[variaga]

You can isolate your ethernet over coax from your neighbor with a MoCA POE "point of entry" filter which blocks the frequencies used by MoCA.

You can buy them online for around $10 and they install without tools,

Besides neighbors, you may also need a POE filter if you have certain types of cable modem.

[tguvot]

cable companies require poe filters. if they find that there is some "noise" leaking from your house, they may put a big filter of their own outside, that can degrade speed of modem