Conferencing, Quality of service – Nortel Networks NN44470-100 User Manual

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MAS commissioning

Nortel Media Application Server 6.0 for AS 5300

Fundamentals

NN44470-100 01.01 Standard

Release 6.0 03 June 2008

— RFC2833

Attention: If you remove all methods, inband DTMF detection is forced,
which is not recommended because it degrades system capacity.

•

Configure the preferred order of enabled DTMF relay methods for
negotiation (SDP answer) or default SDP (SDP offer).

•

Configure the RFC2833 payload type. Nortel recommends that you select
the default payload type, which is determined dynamically. However, some
clients require a fixed payload type.

Conferencing

To configure conferencing, use the Nortel MAS Console. You can configure
the following conferencing properties:

•

Enable or disable the Automatic Gain Control. The default is enabled.

•

Enable or disable the Customized Replacement Video property. When
enabled, customer-supplied replacement video files are used. The default
selection is enabled.

•

Enable or disable the

Lock Video Format on First Party in Conference property.

When enabled, the first party determines the video format. If the first party
is audio-only, the conference has no video. When disabled, the first party
with active video determines the video format. The default is enabled.

•

Enable or disable the Replacement Video For Active Speaker property.
When enabled, the active speaker receives replacement video in
conferences where one or more than two (but not two) parties are enabled
to speak. The default is enabled.

•

For the Silent Conference Teardown Delay (sec) property, configure the
number of seconds a conference must be silent before it is terminated (0
indicates no termination). The default value is one hour.

Quality of Service

MAS supports Differentiated Services (DiffServ) packet marking on outgoing
Real-time Transport Protocol (RTP) streams. The system sets the DiffServ
Control Point (DSCP) to expedited forwarding (EF), which is a widely
supported indicator for QoS-enabled networks carrying real-time audio and
video data. Network routers that are QoS-enabled examine the type of service
bits in the IP header and provide priority (with respect to routing and handling)
to those packets marked with expedited forwarding. In addition to marking
packets, MAS uses high resolution, interrupt-driven timers to drive RTP
packetization at precise intervals.