68 CHAPTER 2: DIAL PLAN
by a firewall. Configure the firewall to allow access to port 25 on the NBX
system only from valid VPIM systems that need to deliver VPIM messages
to the phone system. The NBX SMTP server is started only when the
system has a valid license for VPIM.
To send a voice mail message to a user on another VPIM-compliant
system, an NBX user first composes the voice mail message, using the
commands in the user’s voice mailbox. Depending on how the system’s
dial plan is configured, the user can specify the destination in two ways:
■If the dial plan is configured for site codes, the user specifies the
destination site code followed by the star key (*) and the extension of
the person for whom the voice mail message is intended.
■If the dial plan is configured without site codes, the user specifies the
extension of the person for whom the message is intended. This is
easier, but requires that each site use a unique extension range for
telephones.
■A user who knows the IP address of a VPIM-compliant voice mail
system and the extension of a person who uses that system can
compose a voice mail message and then send it using these steps:
■Dial the IP address, pressing the * key after each field in the
address, including the last field.
■Dial the extension of the person followed by #.
The system administrator configures the dial plan and decides whether to
use site codes or unique extension ranges.
Configuring the Dial Plan for VPIM
To fully define a VPIM connection between two NBX systems, you must
create entries in the dial plan for the following items:
■The digit sequence that a telephone user must dial to access the VPIM
connection
■The route number that is used to access the other NBX system
■The extension list to which the VPIM route belongs
■The operations that must be performed on the dialed digits in order to
create the appropriate outgoing digit sequence