FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
hrahuman_FTNT
Article Id 206881
Description This article describes the difference between 'Security Events' and 'All session' in Log Allowed Traffic in Firewall Policy.
Scope  
Solution

Log 'Security Events' will only log Security (UTM) events (e.g. AV, IPS, firewall web filter), providing you have applied one of them to a firewall (rule) policy.

 

'Log all sessions' will include traffic log include both match and non-match UTM profile defined.