C

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CA

Certification Authority. A service that issues and manages X.509 certificates that can then be used to secure communications, such as browser to server Web transactions or encryption and signing of email messages.

CAL

Client Access License. Every client that connects to Exchange must have a CAL.

CDO

Collaboration Data Objects, a programmable interface designed to make it easier for programmers to manipulate complex objects such as a mailbox or collection of messages.

Child domain

A Windows domain whose DNS name is subordinate to another domain. For example, sales.hp.com is subordinate to the hp.com domain. A child domain is also called a subdomain.

Cluster

A set of individual computers connected together and capable of acting as a single server.

Connection agreement

The specifications for a synchronization link between the AD and the DS. A connection agreement determines exactly what objects are synchronized and when synchronization occurs. It may also determine how new objects are created in a directory and whether any organizational unit remapping occurs.

Container

An Active Directory object that holds groups of objects and other containers.

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