Talk about all the AD-related roles in Windows Server 2008 R2?

Windows Server 2008 has five Active directory related roles. below are the list

1. Active Directory Domain Services (Identity): AD DS it provides the functionality of an identity and access (IDA) solution for enterprise networks. It also provides the mechanisms to support, manage, and configure resources in distribution network environments.

2. Active Directory Lightweight Directory Services (Applications): AD LDS formerly known as Active directory application mode (ADAM), provides support for directory-enabled applications.

3. Active Directory Certificate Services (Trust): AD CS to set up a certificate authority for issuing digital certificates as a part of a public key infrastructure (PKI) that binds the identity of a person, device or service to corresponding private key. Certificates can be used to authenticate users and computers, provide web-based authentication, support smart card authentication, and support application, including secure wireless n/w, vpn, Ipsec, EFS, and more.

4. Active Directory Rights management Services (Integrity): AD RMS is an information-protection technology that enables you to implement persistent usage policy templates (for documents) that define allowed and unauthorized use whether online, offline, inside, or outside the firewall.

5. Active Directory Federation Services (Partnership): AD FS enable an organization to extend IDA across multiple platforms, including both window and non-Windows environments, and to project identity and access rights across security boundaries to trusted partners.