The configuration shown in the exhibit is for a Juniper SRX Series firewall. The session-init parameter is used to control how the firewall processes unknown traffic flows. With the session- init parameter set to 300, any traffic flows that the firewall does not recognize will be dropped after 300 milliseconds. Additionally, every session that enters the device, whether it is known or unknown, will generate an event, which can be used for logging and troubleshooting purposes.
The session-lose parameter is used to control how the firewall handles established sessions that are terminated.

Explanation
References:
Security Policies Feature Guide for Security Devices
Application Security User Guide for Security Devices
Understanding Micro Application Detection
Configuring Micro Application Detection
Content Filtering Feature Guide for Security Devices

you need to create a global firewall rulebase that matches RT_FLOW_SESSION_DENY events2. To do this, you need to specify two policy parameters: deny and session-close3.