Community edition is free and licensed under the AGPL.
Enterprise version is commercial.
You get a license for 20 devices when using Enterprise for free (once you activate it). You may need to log off, restart the omkd service and log back on to force the footer to update (assuming you have activated a free 20 device license).
Running Discovery and Reporting, etc from Enterprise with the free (20 device) license limits everything in Enterprise to 20 devices.
You can use Community on unlimited devices.
They are two completely different applications. They look different. You access them art different URLs.
Community -
http://YOUR_SERVER/open-audit/index.phpEnterprise -
http://YOUR_SERVER/omk/oaeEnterprise is designed to utilise Community and it's data - as well as build on top of it. Features like Baselines, Map, Dashboard, Scheduled Reports, Scheduled Discovery, etc are only available in Enterprise.
There also a wiki page on this - [url]https://community.opmantek.com/display/OA/Open-AudIT+Community+versus+Enterprise[/url] and a lot of other documentation on the wiki as well - [url]https://community.opmantek.com/display/OA/Home[/url].
Hope that's cleared it up somewhat.