User groups subsystem

Multi level user groups (e.g. supergroup, group, mini-group). Related to messaging and knowledge base subsystems.

Group types

Super group (e.g. Forum)
Regular group (e.g. Forum topic)
Mini group (e.g. Topic theme)

Group access

Public
Logged (e.g. user should be logged in the system)
Logged into parent group (if parent group requires separate auth)
By request
By invitation