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Glossary of Features
Accept Incoming Calls
This feature allows the gateway to answer an incoming call from the PSTN. The gateway then makes a
SIP call to extension 10000.
Accept Outgoing Calls
An outgoing SIP call from the UC server results in an outgoing PSTN call.
Active Message Delivery
The gateway must support the UC server calling out to the PSTN to deliver voice messages.
Answer Supervision
The gateway must detect that a call has been answered. There are a number of techniques used for this,
including loop start, battery reversal and voice detection.
Calling Party Name
The gateway detects the calling party name on an incoming PSTN call and provides that name to the UC
server.
Conferencing with SIP Endpoints
The gateway needs to support conferencing between itself and other SIP endpoints.
Direct Inward Dialing
Calls incoming from the PSTN must be automatically routed to the UC server for auto attendant
functionality.
Disconnect Detection
The gateway must detect that a call has been dropped. There are a number of techniques used for this,
including loop start, battery reversal and no voice detection.
DTMF Tone Support (RFC2833 Compliant)
Calls incoming from the PSTN to the UC server are usually handled by an auto attendant. Feature
operation is implemented using DTMF tones from telephones. These tones must be sent to the UC server
as SIP packets via RFC2833.
Incoming Fax Support
The UC server supports the transmission of faxes to standard fax machines. The gateway must support
T.38 fax transport to provide this capability. Additionally, the gateway should support CNG tones so that
an incoming PSTN fax call can be distinguished from a voice call and handled appropriately.
Multiple SIP Proxy Support
In high reliability applications, if the main UC server is not available the gateway routes incoming PSTN
calls to an alternative SIP Proxy.
