The IBM i doesn’t come with its own out-of-the-box firewall, as you would find with stand-alone network firewalls or other servers.

IBM instead offers exit points that are activated from inside operating system requests such as Telnet & FTP sign-ons. 

SEA’s in-depth guide explains how to use exit points to enable IBM i firewall capabilities and extend functionality including: 

• Understanding what IBM i exit points are, how they work and why they are critical to IBM i security
• Key considerations and common problems with using exit point programming
• The benefits of using third-party solutions for exit point management over creating your own exit point programs
• Commonly used IBM i exit points for increased security