Carrier Access CMG Router User Manual
Page 82
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CMG Router - Release 2.7
Profile Directory:Router Card Profile
Voice Channels
Type of Service
- Defines the default value for the Type of Service (TOS) in the IP header of
outgoing VoIP packets for the specified channel. The initial default is zero. The definition of the TOS
byte is provided in IETF RFC 791 for the original method of packet classification, and in RFC 2474
for the differentiated service method of classification. In the original classification scheme, the first
(leftmost) 3 bits of the TOS byte represents the "precedence" or priority. Bit 4 (from the left) indicates
optimize for delay. Bit 5 indicates optimize for throughput. Bit 6 indicated optimize for reliability.
DTMF Relay
- Enables or disables the relay of DTMF packets as per RFC 2833.
Slash
- Removes implied slash between endpoint and suffix and prefix.
Calling Party Disc
- Requests that calling party disconnect be played automatically to an
endpoint after the last connection on that endpoint is deleted.
Fax
- Sets the fax handling for this endpoint.
Note: For the Fax to operate the following must be set:
CMG G.729A feature must be enabled, with a software key
Specified voice channel has Fax configured as T38reserved or T38
G.729A codec is enabled
the only codec that will result in good fax and modem calls. In this mode echo cancellation must
be OFF for modem calls, and ON for fax calls.
controlled fax bypass using NSEs). After a call is connected to the channel in voice mode, if a fax
tone is detected on the channel, the CMG will transmit NSEs to the remote gateway to tell it to switch
to a G.711 codec and then it will switch to a G.711 codec itself for that channel and disable silence
suppression. For the switchover to be successful, the remote gateway must also switchover to G.711.
The form of G.711 (mu-law or A-law) to which the codec is switched will be the form which has the
highest priority in the negotiated codec list. Note: Either G711mu or G711a must be on the
algorithm preference list for Fax Bypass to work.
T.38 fax relay using NSEs) if DSP resources are available. When no DSP resources are available
(6 active T.38 fax calls) the card will reject the T.38 connect request and revert the channel to fax
bypass mode using the G.711 codec.