Matrix ETERNITY NE - Page 151

Matrix ETERNITY NE System Manual 141
• Select Echo Cancellation Tail Length (msec) for CO trunks. It may be 32, 64, or 128 milliseconds.
Default: 128. milliseconds.
• Select Echo Cancellation Tail Length (msec) for Extensions and Digital Trunks. It may be 32, 64, or
128 milliseconds. Default: 32 milliseconds.
14. Configure Jitter Buffer
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to cut down on packet delays and improve voice quality.
• Select the Type of Jitter Buffer you want to use: Static or Dynamic. Default: Dynamic.
Static Jitter Buffer's internal delay is static, whereas, the Dynamic Jitter Buffer's internal delay adapts
itself to the jitter in the network.
• If you selected Static Jitter Buffer, configure Minimum Delay
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, from 10 to 280 milliseconds. Default 10
milliseconds.
The value configured in the Minimum Delay determines the size of the Static Jitter buffer.
• If you selected Dynamic Jitter Buffer, configure Minimum Delay
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and Optimization Factor, from 1 to
13. Default: 10. By default Minimum Delay is set to 10 milliseconds.
The Optimization Factor determines the rate of adaptation of the Dynamic Jitter Buffer to the jitter in the
network. The minimum size of the Dynamic Jitter buffer depends on the 'Minimum Delay' configured.
In networks with higher jitter, a higher value should be configured as Optimization Factor.
The actual size of the Dynamic Jitter Buffer will be determined by the DSP on the basis of the
Optimization Factor configured and actual network condition. Dynamic Jitter buffer can go up to
maximum 300 milliseconds.
15. If you are using Fax over IP (FoIP)
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, select the protocol as Fax Type. You may select:
• T.38 (UDPTL)
• T.38 (RTP)
• Pass-through.
Default: T.38 (UDPTL)
• 'Pass Through' and 'T.38' will work only if the peer devices also support the same option.
• If you select 'Pass through' as Fax type, you must disable 'Silence Suppression'.
• If the fax sent using T.38 is rejected, ETERNITY NE will use Pass Through for sending the Fax.
16. If you selected T.38 as Fax Type, configure T.38 Fax Parameters.
35. The speed at which voice packets travel through a network depends on the condition of the network. All voice packets may not
come at the same speed. This variation in the delay in receiving packets, known as Jitter, affects voice quality. Jitter Buffer helps
overcome the delay in receiving voice packets and improves voice quality. Jitter Buffer receives voice packets, stores them and
sends it to the DSP to process it at evenly spaced intervals, thus improving voice quality.
36. This parameter is to be configured for both Static and Dynamic Jitter Buffer. The Minimum Delay determines the size of the Static
Jitter Buffer and when Jitter Buffer type is Static, the Minimum Delay defines the size of the Static Jitter Buffer. 'Minimum Delay'
can be from 10 to 280 milliseconds. By default Minimum Delay is set to 10 milliseconds. The Static Jitter Buffer will store each
received voice packets for the configured time and then it will send it to DSP for voice processing.
37. When Jitter Buffer type is Dynamic, the Minimum Delay specifies the minimum time for which the Dynamic Jitter Buffer will store
the received voice packet before sending it to the DSP for voice processing.
38. You can send/receive Fax, by connecting a fax machine to the SLT port of ETERNITY NE.