Cisco
Configuration Tasks
Voice Quality Tuning Commands
The commands in this section configure parameters to improve voice quality. Common voice quality issues include the following:
•Configuring Adaptive Jitter Adjustment (optional)
•Configuring Echo Adjustment (optional)
•Configuring Voice Level Adjustment (optional)
Configuring Adaptive Jitter Adjustment
To configure the playout delay jitter buffer, use the following commands beginning in
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Determines the mode in which the jitter buffer will | ||||
| fixed} | operate for calls on this voice port. | ||
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| The keywords are as follows: |
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| amount of playout delay during a call based on |
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| current network conditions. |
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| that the playout delay does not adjust during a |
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| call. A constant playout delay is added. |
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| The default is adaptive. |
Step 2 |
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Tunes the playout buffer to accommodate packet | ||||
| maximum value minimum {default low high}} | jitter caused by switches in the WAN. | ||
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| The keywords and arguments are as follows: |
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| delay applied at the beginning of a call by the |
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| jitter buffer in the gateway. In fixed mode, this |
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| is also the maximum size of the jitter buffer |
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| throughout the call. |
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| type of DSP and configured codec complexity. |
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| For medium codec complexity, the range is |
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| from 0 to 150 ms. For high codec complexity |
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| and DSPs that do not support codec |
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| complexity, the range is from 0 to 250 ms. |
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| • maximum (adaptive mode |
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| the jitter buffer's upper limit (80 ms), or the |
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| highest value to which the adaptive delay is set. |
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| • minimum (adaptive mode |
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| the jitter buffer's lower limit (10 ms), or the |
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| lowest value to which the adaptive delay is set. |
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| Cisco IOS Release 12.2(2)XT and 12.2(8)T |
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