Aastra Telecom Pro 160 User Manual

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Configuring VoIP Settings
41-001190-01 Rel. 1.1, Rev. 00
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Configuring AastraLink Pro 160 System and Network Parameters
SIP Direct Inward Dialing (DID)
An administrator can provide SIP Direct Inward Dialing (DID) prefixes for SIP 
trunks. Direct Inward Dialing (DID) is a service of a local phone company that 
provides a block of telephone numbers for calling into a company's private branch 
exchange (PBX) system. 
Using DID, a company can offer its employees a different direct-dial PSTN  
number for each SIP phone, with either system-wide DID pattern matching or 
direct-mapped user DID entries used to route calls.
This feature on the VoIP Menu applies on a global basis for all phones in the 
AastraLink network.
Note: 
Direct mapping DIDs have highest priority, followed by patterns, and then the Interactive 
Voice Response (IVR) if no DID is matched. SIP DID mapping can also be applied on a 
phone-by-phone basis using the SIP DID Number parameter when editing or adding phones on the 
Users Menu.