phone directory
The mobile phone (also called a mobile, wireless, cellular phone, cell phone, or hand phone(hp)) is a short-range, portable electronic device used for mobile voice or data communication over a network of specialized base stations known as cell sites. In addition to the standard voice function of a telephone, current mobile phones may support many additional services, and accessories, such as SMS for text messaging, email, packet switching for access to the Internet, and MMS for sending and receiving photos and video. Most current mobile phones connect to a cellular network of base stations (cell sites), which is in turn interconnected to the public switched telephone network (PSTN) (the exception is satellite phones). Since the mid-2000s, an increasing number of cellphones can connect to the Internet, a portion of which can be navigated using cellphones.
Active Directory ( AD ) is an implementation of LDAP directory services by Microsoft for use primarily in Windows environments. Its main purpose is to provide central authentication and authorization services for Windows-based computers. Active Directory also allows administrators to assign policies, deploy software, and apply critical updates to an organization. Active Directory stores information and settings in a central database. Active Directory networks can vary from a small installation with a few hundred objects, to a large installation with millions of objects.
Active Directory was previewed in 1996, released first with Windows 2000 Server edition, and revised to extend functionality and improve administration in Windows Server 2003. Additional improvements were made in both Windows Server 2003 R2 and Windows Server 2008.
Active Directory was called NTDS (NT Directory Service) in older Microsoft documents. This name can still be seen in some AD binaries.
There is a common misconception that Active Directory provides software distribution. Software distribution is run by a separate service that uses additional proprietary schema attributes that work in conjunction with the LDAP protocol. Active Directory does not automate software distribution, but provides a mechanism in which other services can provide software distribution.