I recommend reading the likes of https://security.stackexchange.com/questions/8772/ https://security.stackexchange.com/questions/8772/ , https://superuser.com/q

I recommend reading the likes of https://security.stackexchange.com/questions/8772/ https://security.stackexchange.com/questions/8772/ , https://superuser.com/questions/237790/ https://superuser.com/questions/237790/ , https://security.stackexchange.com/questions/155159/ https://security.stackexchange.com/questions/155159/ , https://f5.com/resources/white-papers/the-myth-of-network-address-translation-as-security https://f5.com/resources/white-papers/the-myth-of-network-ad... , and a lot of other writings in this vein.