Cisco Systems SPA9000 Supporting Direct Inward Dialing to Phone Extensions, Example SIP Header

Configuring Phone Lines and Calling Routing Behavior	4
Managing Inbound Calls with the Contact List

EXAMPLE SIP Header 1:

INVITE sip:4089993000@itsp1.com SIP/2.0

To: <sip:4089993003@itsp1.com>

Alternatively, the DID number can be indicated as a parameter in the TO header with a configurable parameter name, such as didn.

EXAMPLE SIP Header 2:

INVITE sip:4089993000@itsp1.com SIP/2.0

To: <sip:4089993000@itsp1.com>;didn=4089993003

You can identify the field to use for the DID number and the parameter name on the Voice > SIP page, PBX Parameters section, SIP DIDN and SIP DIDN Param Name fields. For the first example above, these two fields are ignored; for the second example, SIP DIDN is set to TO Param and SIP DIDN Param Name is set to didn.

The Contact List is used to route the calls to a client station based on DID numbers that are embedded in the INVITE message.

EXAMPLE Contact List Rule:

4089993000:aa4089993001:30014089993002:3002…4089993009:3

009

An incoming call to the main number is answered by the Auto-Attendant, while calls to the other nine DID numbers are routed to dedicated private extensions.

Supporting Direct Inward Dialing to Phone Extensions

Direct Inward Dialing allows the external users to dial directly any phone extension in the SPA9000 Voice System, without passing through the Auto Attendant or the receptionist.

Before proceeding with the configuration you need to have the full correspondence between the external (DID) number and the extension number. Table 1, “DID-to-Extension Mapping Example,” on page 89 provides an example.

SPA9000 Voice System Administration Guide 88