A horizontal pattern must have a TCP entry point type or an ALL entry point type to execute from a process classifier. A process classifier is a rule that matches a process running on a host and triggers a horizontal pattern to discover the application associated with that process1. The entry point type determines the type of connection that the pattern uses to access the target host. A TCP entry point type means that the pattern uses a TCP port to connect to the host, while an ALL entry point type means that the pattern can use any available connection method2.