A firewall application prevents unsafe network (and internet) connections from being established between your Mac and other computers. Surprisingly, a Mac’s firewall application is disabled by default. This leaves your computer vulnerable to attack on any public or university network.
Activate the Mac firewall application by …
- Click the Apple logo in the top left corner of the screen.
- Now click on “System Preferences”.
- Click “Security & Privacy”
- Now select the “Firewall” tab.
- Click “Turn On Firewall”
- And then close “System Preferences”
- That’s it!