Difference: Optimum Proactive Defense/Maximum Proactive Defense +

Hello.

When installing only firewall.
Have choise “Firewall with Optimum Proactive Defense” or “Firewall with Maximum Proactive Defense +”.

What is difference ?
Just defense+ setting to “Paranoid Mode” ?
And firewall to “Custom ¨Policy Mode” ?
Or installing something more ?
When “Firewall with Maximum Proactive Defense +” is check.

Thanks.