Specifications

Chapter 4 - MGCP Protocol Features Interoperability Configuration
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Mediatrix 4100
T.38 Capabilities Using Audio Codec 98
You can enable or disable the parsing of remote SDP in order to extract remote T.38 capabilities from an audio
stream. This is useful when a call agent is re-using the audio stream to advertise the remote T.38 capabilities
instead of creating a new image stream.
 To enable T.38 capabilities using audio codec 98:
1. In the mgcpncsExperimentalMIB, set the mgcpncsT38CapabilitiesUsingAudioCodec98 variable to
enable.
The Mediatrix 4100 verifies the remote SDP audio stream for the T.38 port number. The remote
SDP must meet the following conditions in order to detect T.38 capabilities from the audio stream:
• Single audio stream
• Single media format 98
• No rtpmaps
If the variable is set to disable, the call agent never uses the audio stream to advertise the remote
T.38 port number.
Immediate Modem Tone Reporting
You can control whether the early detection of a modem tone by the Mediatrix 4100 is immediately reported
to the call agent (when requested) or delayed until the exact nature of the transmission has been determined.
Some fax transmissions begin by exchanging modem tones in their setup stage; therefore, a little time is
needed before the Mediatrix 4100 is able to discriminate between a fax or a modem transmission.
 To enable immediate modem tone reporting:
1. In the mgcpncsExperimentalMIB, set the mgcpncsImmediateModemToneReporting variable as
required.
Brief OSI Signal
For legacy reasons, you can change the behaviour of the Network Disconnect signal (L/osi) by changing its
type from time-out to brief (see RFC 3435 for a description of the various signal types).
 To make the OSI signal brief:
1. In the mgcpncsExperimentalMIB, set the mgcpncsMakeOsiSignalBrief variable as required.
Table 60: Modem Tone Reporting Parameters
Parameter Description
enable The Mediatrix 4100 will report a modem tone to the call agent (assuming the call
agent has requested it) as soon as it detects one.
disable The Mediatrix 4100 will wait until it has determined the exact nature of a data
transmission and then report either a fax or a modem tone to the call agent (always
assuming the call agent has requested it).
Table 61: Brief OSI Signal Parameters
Parameter Description
enable The L/osi signal will behave like a brief signal.
disable The L/osi signal conforms to its standard definition and behaves like a time-out
signal.