Ambit U10C034, User Manual

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U10C034 Telephony Version v1.4 June 2008
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2.2.4 Software Upgrade During Calls
brcm-cm-mgmt-ext.mib
MIB Default Value Access
emtaInhibitSwDownloadDuringCall False read-write
emtaInhibitSwDownloadDuringCall
(1.3.6.1.4.1.4413.2.2.2.1.6.1.1.0 Integer32)
This object controls the processing logic of software downloading requests
when there are specific telephony related EMTA activities. If this object
has a value of true(1), DOCSIS software download by way of the
docsDevSwAdminStatus MIB object will be inhibited if the value of
esafeDevServiceIntImpact for the eMTA entry has a value of significant(1),
indicating a call in progress. If docsDevSwAdminStatus is set to
upgradeFromMgt(1) under these conditions, an error code of
resourceUnavailable(13) will be returned and an appropriate event logged
to the CM.
2.2.5 Configuring the Jitter Buffer
There are 4 MIBs that constitute the control of the jitter buffer which can be
configured as either fixed or adaptive by the emtaSignalingVoiceJitterBufferType
MIB. The jitter buffer holds RTP frames for a configurable period of time in order
to smooth out network jitter. In the case of a fixed jitter buffer the frames are held
for a fixed period of time. A fixed jitter buffer with a high holding period is
appropriate for VBD because delay is not as important as reducing packet loss,
but in the case of voice calls where minimizing delay is more important than
reducing packet loss an adaptive jitter buffer is appropriate. The adaptive jitter
buffer adjusts the holding time as required based on the detected network jitter.
The default values controlling the jitter buffer are for an adaptive jitter buffer with
a maximum hold time of 200ms. The MIB default of 0 for
emtaSignalingVoiceJitterBufferNomValue and
emtaSignalingVoiceJitterBufferMinValue means they can adjust up to the
maximum which is 200ms. The nominal hold time will be adjusted immediately
when a voice call starts up. If you freeze the voice jitter buffer it uses the
emtaSignalingVoiceJitterNomValue for the fixed size of the jitter buffer.
There are three MIBs for configuring the jitter buffer:
•
emtaSignalingVoiceJitterNomValue
•
emtaSignalingVoiceJitterMinValue
•
emtaSignalingVoiceJitterMaxValue
brcm-emta-mgmt.mib