The UM components enable the integration of Unified Messaging into your directory structure and your existing telephony infrastructure. Your directory stores all the components and settings for UM. Each UM component is necessary to support Unified Messaging. Some UM components are created to represent a telephony hardware device. Others are created to represent a telephony dial plan for an organization or to support a specific feature of Unified Messaging.

There's a tightly integrated and interconnected relationship between the UM components and the features available in Unified Messaging. To successfully plan and deploy Unified Messaging in your organization, you need to fully understand the relationship between each UM component and the others.

For more information about the UM components, see:

• UM Dial Plans
  
  
• UM IP Gateways
  
  
• Automatically Answer and Route Incoming Calls
  
  
• Voice Mail for Users