central network management in Linux/Unix

I was always curious how a Linux/Unix network would be centrally managed.

In the Windows world there is Active Directory which is based on LDAP. Which creates domains and domain authentication for users.

I know SAMBA can act as a domain controller and all that, but I'm not interested in making Linux act like Windows, I want to know what the Linux/Unix approach would be.
Or would you simply use another LDAP based tool on a purely Linux/Unix network too?
I also thought about NIS/NIS+ but that seems to have fallen by the wayside, or is it still a popular solution?

Linux has OpenLDAP which performs the same sort of services as does Microsoft's Active Directory, but not encumbered with Microsoft's proprietary extensions. There is also NIS/NIS+ (so-called Yellow Pages), but those are more for use in combined legacy Unix/Linux environments - there are a lot of organizations that still use it because the cost/pain to migrate is too much to bear. As the old saying goes, if it ain't broke, then don't fix it! :-)