15	Numbers and Number Mappings
          A flexible number concept, which supports distributed locations
          The 
number mapping explained in this chapter describes the mapping of internal numbers for a user to external call numbers. 
Number mapping should not be confused with the number replacement which can be defined on a trunk group. Number replacement specifies how numbers (number ranges) can be replaced by other numbers/ranges (
8.7.1 Defining call number substitutions for a trunk group).
 
          In this context, please note the following definitions: 
Forwardings are in relation to a trunk group and establish whether a call via this trunk group can fundamentally leave the SwyxWare installation (
8.7 Forwarding and number substitution). The 
call permission for a user or a trunk group defines whether a call has the right to be made via this trunk group (
8.2 Edit trunk groups).