Which of the following methods of protection is not available within the Protocol Security Manager for FTP protection?

Session timeout is not configurable within the Protocol Security Manager FTP profile - timeout behavior is governed by other BIG-IP profile settings such as the TCP or connection profile, not the FTP security profile.

Command length is a valid FTP protection option in Protocol Security Manager, enabling administrators to cap FTP command length and mitigate buffer overflow attempts.

Allowed commands is a valid FTP protection option that restricts which FTP commands may be issued, blocking any command not on the permitted list.

Anonymous FTP restriction is a valid protection option that allows administrators to block or limit anonymous FTP logins to reduce unauthorized access risk.