Authentication response filter - Postgres
An AuthenticationRequest packet (which is really a response because it's sent by the server) is sent by the database server after receiving a StartupMessage from the client. There are several different types of authentication requests, depending on the authentication methods supported by your Postgres server (see Postgres documentation for details).
The authentication response filter allows you to easily intercept these types of packets. It can be configured to specify which kind should result in execution of the filter: