Also check the AlienVault Forum for USM Appliance Release Notes.
OSSIM Limitations: Because AlienVault OSSIM™ includes a subset of USM Appliance's capabilities, we've indicated which topics also apply to AlienVault OSSIM throughout the Deployment Guide and User Guide. If a topic applies to AlienVault OSSIM, you will see the AlienVault OSSIM logo highlighted in green in the Applies to Product header on each page, like in the image below:
If there are limitations to the capabilities in AlienVault OSSIM compared to USM Appliance, those limitations will be listed at the bottom of the page. If the capabilities described are not available in AlienVault OSSIM, the AlienVault OSSIM logo will appear in gray.
When looking for AlienVault OSSIM documentation, type the keywords in the search box and choose "OSSIM" from the All Files list to limit your search.