Medias Mediatrix 1204, Справочное руководство

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Chapter 5 - Web Interface – Telephony Voice & Fax Codecs
84 Mediatrix 1204
8. Set the payload type in the DTMF Payload Type field.
You can determine the actual RTP dynamic payload type used for the “telephone-event” in an initial
offer. The payload types available are as per RFC 1890. Available values range from 96 to 127.
9. Set the RTP Base Port field with the port number you want to use as RTP/RTCP base port.
The RTP/RTCP ports are allocated starting from the base port. The Mediatrix 1204 may use two or
four RTP/RTCP ports for each FXS interface:
• It uses two ports in case of a standard call.
• It uses four ports in other types of calls such as a conference call, a call transfer, etc.
The default RTP/RTCP base port is 5004 . In the case of the base port defined on 5004:
• If there is currently no ongoing call and FXS connector 1 has an incoming or outgoing
call, it uses the RTP/RTCP ports 5004 and 5005.
• If there is currently a standard call on FXS connector 1 and FXS connector 2 has a
conference call, then FXS connector 2 uses the RTP/RTCP ports 5006, 5007, 5008,
and 5009, which are the next available ports.
10. Click Submit if you do not need to set other parameters.
About Changing Jitter Buffer Values
Mediatrix recommends to avoid changing the target and maximum jitter buffer values unless experiencing or
strongly expecting one of the following symptoms:
If the voice is scattered and a lot of jitter buffer events are received when the syslog is enabled,
try to increase the maximum jitter buffer value.
If the delay in the voice path (end to end) is too long, you can lower the target jitter value, but
ONLY if the end-to-end delay measured matches the target jitter value.
For instance, if the target jitter value is 50 ms, the maximum jitter is 300 ms and the delay measured
is 260 ms, it would serve nothing to reduce the target jitter. However, if the target jitter value is
100 ms and the measured delay is between 100 ms and 110 ms, then you can lower the target jitter
from 50 ms to 30 ms.
Note:
This parameter applies only when selecting the outOfBandUsingRtp DTMF transport mode.