PHP on Linux authenticate users with a Windows Server Active Directory 2

PHP on Linux authenticate users with a Windows Server Active Directory
A common request when building INTRANET web applications is to have users use only one  common shared set of  login credentials. Typically in most small and medium businesses this means that logging into a Windows Server of some kind to access the network.  Windows Servers use Active Directory (AD) ,which is  basically Microsoft’s glorified LDAP ...