Know yourself, including your methods and their limitations; nothing to excess, and certainty brings insanity: the maxims for those who study macOS.
firewall
What are ports in networking, and where would you find them? What use are they apart from making networking more confusing?
Certificate revocation checks in macOS could be misused in surveillance. How could you prevent that without putting your Mac at risk?
Using Little Snitch, this becomes unresolvable, as the app can’t complete first run checks, and every time you try, it’s translocated to a different folder, causing Little Snitch to block it again.
Making your network more secure using software firewalls and SSL inspection can block macOS from functioning properly.
Over a million people learned that very personal details of their had been leaking from an unsecured server. What should we learn?
Mac users are increasingly using software firewalls to prevent apps from making outgoing connections. Here are some tips, and links to help you build whitelists.
Further suggestions for setting your router up, to keep your local network safe, secure, and free from trouble.
The lights on my cable modem flash even when the network is shut down. How should I protect myself?
Is Little Snitch good protection against malware?
The Eclectic Light Company 