4-/8-/16-/24-/32-Port SIP Internet Telephony Gateway
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3.8.2
Media Parameter
Media parameters mainly include: RTP start port, DTMF parameter, Preferred Vocoder, etc.
Figure 3.10-2 Configuration Interface for Media Parameters
Explanation of media parameters:
Use Random Port
If this parameter is enabled, the gateway will choose a port at random as the start
port for RTP.
RTP Start Port
Default RTP start port is 8000
DTMF Method
Include SINGAL, INBAND and RFC2833
RFC2833 Payload Type
Payload value, default value is 101
DTMF Gain
Default value is 0 DB
DTMF Send Interval
The interval for sending DTMF signal. The default value is 200ms.
Send Flash Event
If this parameter is enabled, the gateway will send flash event to remote terminal,
and thus user does need to handle it locally
Coder Name
The gateway supports G729, G711U, G711A and G723. When outgoing calls are
made, G.729 will be used.
Payload Type
Each kind of coding has a unique load value in reference to RFC3551.
Packetization Time
The time for voice packaging
Rate
Voice data flow rate defaulted by system.
Silence Suppression
Default value is ‘disabled’. If this parameter is enabled, VoIP transmission
bandwidth can be saved, and meanwhile network congestion can be avoided.