Routing Mailboxes are a category of mailboxes normally used to route Automated Attendant calls. A
Routing Mailbox can be an Announcement Mailbox, a Call Routing Mailbox, a Directory Dialing Mailbox,
or a Distribution Mailbox. See the following for more on each of the Routing Mailbox types:
The Call Routing Mailbox, associated with an Answer Table, specifies which dialing
options (Dial Action Table) and announcements are available to Automated Attendant
callers.