What does the Custom PAC URL reference in the ZIA Admin Portal?

The Custom PAC URL in the ZIA Admin Portal specifically references the Proxy Auto-Configuration (PAC) file, which is utilized for traffic decisions to determine how web traffic should be routed based on various parameters such as the destination URL, user location, and network conditions. By providing a Custom PAC URL, administrators can direct users to a specific PAC file that outlines these routing rules, enabling dynamic configuration for how requests are handled.

This is particularly important in scenarios where network traffic needs to be routed through the Zscaler platform for security, performance optimization, or compliance purposes. The PAC file contains the logic used by web browsers to decide whether to send a request directly to the destination server or through a proxy server. Therefore, setting a Custom PAC URL allows administrators to tailor the traffic management strategy suitable to their organization's needs.