I am having a very tough time figuring out the permissions in my database. My users gain access to the database through reports on SharePoint (via Impersonated authentication configured through Kerberos). Users, who are impersonated, are all added to AD Groups. And in my database, I am granting permissions to the AD GROUPS (as logins) and NOT to the individual users. I have 1000 users but 10 AD Groups. Each user is part of an AD Group. The users currently cannot have access to the database – they are only able to see the database if I was to add them individually as logins (obviously not an option). If I add their AD Group, it doesn’t seem like it works. Again, they are authenticated through Kerberos as impersonated accounts. Here is a map of what I’m saying: IF the AD GROUP has permission, why doesn't the user within has permission?? I reviewed this question, but I'm not sure where is the equivalent for SharePoint Integrated mode.
EDIT: In case it makes a difference, AD Groups are assigned as "Security Group - Universal"