The dial plan is the essence of a Unified Communications (UC) system. The dial plan is at the core of the end user experience because it defines the rules that govern how a user can dial a public switched telephone network (PSTN) destination.
Endpoint addressing is an important part of the internal dial plan, which is normally segregated but directly related to the external PSTN dial plan required when calling from devices external to the organization.
Digit analysis and path selection are also important components of a dial plan. This chapter describes endpoint addressing, digit analysis (DA), and call-routing path selection in a Cisco Unified Communications Manager (CUCM) deployment.