central sign-on for Red Hat?

["Angie Moore" <diabeticithink yahoo com>]

Hi All
 
Is there a way to have all of my users (25 red hat boxes on RHES 4.0), to
have their logon accounts and permission managed and configured from one
server (like Active Directory does)? Would OpenLDAP do the trick? Or is
there another way? 
 
As always, thank you for your help!
 
Anne