Snom ONE IP Technical Manual page 140

Deploying the snom ONE IP Telephone System
120
If the setting includes regular expressions, the system will route the call accord-
ingly (see "When Regular Expressions are Involved" on page 121). When
using regular expressions in the Send call to extension field, it is important
to provide a default extension in the event the replacement pattern does not
produce an existing extension (in the example shown below, 777 is the fallback
extension).
2. If nothing was set in the trunk's Send call to extension setting, the system must
go to the individual extensions to determine whether the called number is asso-
ciated with any account. Using the example shown below, if the number dialed
8124351234
was
incoming number and will route the call accordingly. If no extension is associ-
ated with the incoming number, the call will fail.
The number shown to the right of the extension is known as a DID. This meth-
od of attaching a DID to an extension is a viable routing method only when
the number of DIDs is small (e.g., four to ten DIDs). When a large number of
DIDs are involved, using regular expressions in the trunk's Send call to exten-
sion field is a better approach (page 121).
Corresponding Log File and SIP Trace
This section provides a few SIP traces that correspond to the settings shown in the pre-
vious section ("Basic Routing"). When a call has been routed to an extension through
the Send call to extension setting, the system writes a log (Figure 4-10) with the mes-
sage Trunk <name> sends call to ...
Figure 4-10. Log File Reflecting "Call to extension" Setting
, the system will see that extension 508 is associated with the
into the log file (log level 5).