Comrex Access NX, Руководство по эксплуатации продукта

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Delay Limit - The Delay Limit instruct the jitter buffer manager to not “wind” the buffer out beyond a certain
delay value, regardless of how many packets are lost. This is useful in applications where staying below a certain
delay figure is essential. However, use of the delay limit can result in very poor performance if the network jitter
dramatically exceeds the set limit.
Jitter Window - This parameter defines the amount of time (in minutes) that historical network performance is
analyzed. The result is used to make the rest of the calculations. As an example, if the Jitter Window is set to the
default of five minutes, and if a dramatic network event happens that causes the buffer to react by increasing
the buffer size, the event will be included in the manager’s calculations for the next five minutes. If the network
experiences improved performance, the manager may choose to wind the buffer back down after the five minutes
has passed.
Buffer Management On/Off - This option is available only as a troubleshooting tool. Turning the buffer manager off
will result in eventual failure, since the manager compensates for clock skew between the encoder and decoder.
CrossLock Managed Delay - By default, the buffer manager finds its own delay target. The CrossLock layer also
calculates a delay target that is generally more conservative, and this option allows that target number to be used.
Our testing shows best results with the default delay target.
Log Statistics - This function is used in factory diagnostics and should be left disabled unless instructed to be
changed by Comrex support.
Congestion Avoidance - Enabling this option allows the encoder to dynamically change the number of frames per
packet sent, thereby reducing total data requirements. In addition, in most encode modes, enabling Congestion
Avoidance provides the system with the ability to step down to a lower encode data rate if desired. This will
happen automatically and with no audio interruption. NOTE: Step down congestion avoidance is not enabled in
Linear PCM modes.