What is the purpose of "Application Override Policies" in Palo Alto Networks firewalls?

The purpose of "Application Override Policies" in Palo Alto Networks firewalls is to bypass the default App-ID signatures for specific applications. This feature allows network administrators to define rules for applications that may not be accurately identified by the firewall's default App-ID database due to encryption, tunneling, or other reasons that obscure application traffic.

By using application override policies, organizations can create specific rules that identify applications based on layer 4 (transport layer) characteristics, such as source and destination IP addresses, ports, and protocols, rather than relying on deep packet inspection. This is particularly useful for ensuring critical applications are recognized and treated appropriately, even when they do not conform to the usual identification methods.

This approach helps to maintain application visibility and control while allowing the firewall to manage traffic effectively. Such policies can enhance performance, ensure proper functionality of specific applications, and allow for customized handling in environments where default App-ID may fall short.