What happens when a Junos firewall filter permits the initial connection?

When a Junos firewall filter permits the initial connection, it automatically permits bidirectional communications. This behavior is a result of the stateful processing capabilities of the firewall. When a new session is established and the initial packet is permitted by the filter, the firewall maintains a session state for that connection.

As a result, once the initial connection is allowed, the subsequent packets belonging to that session, whether inbound or outbound, are automatically permitted without requiring additional checks through the firewall filters. This means that the stateful firewall can track the connection and ensure that traffic for that session is allowed in both directions, making network communication more efficient and manageable.

In contrast, options that suggest tracking every packet individually or requiring additional configuration for each connection do not align with how stateful firewalls operate, as they utilize session states to allow seamless communication once a connection is established. The notion that processing stops once the initial connection is established is also misleading, as the firewall continues to manage the session while it is active.