Multitech MultiVOIP 200 MVP200, Руководство пользователя

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MultiVOIP 200 User Guide
10. To change the voice coder, first select the channel by clicking the Select Channel down arrow
(highlighting the channel number) then click Manual in the Coder group. To select the appropriate
coder, click the Selected Coder down arrow and highlight your new voice coder entry.
If you changed the voice coder, ensure that the same voice coder is used on the voice/fax
channel you are calling; otherwise, you will always get a busy signal.
Note: If you allow the Coder to be selected automatically, then you need to select the Max
Bandwidth from the drop-down list. Check with your VOIP administrator to determine how much
bandwidth is available.
11. The Fax group enables you to send/receive faxes on the selected voice/fax channel. You can set
the maximum baud rate for faxes and the fax volume in the two drop-down lists and change the
jitter value in milliseconds.
When receiving fax packets from a remote MultiVOIP 200, it is possible for individual packets to
be delayed or received out of order due to traffic conditions on the network. To compensate for
this effect, the MultiVOIP 200 uses a Jitter Buffer. The Jitter Value field allows the MultiVOIP 200
to wait a user-definable period of time, in milliseconds, for delayed or out of order fax packets.
The range of allowable Jitter Values is 0 to 400 with a default of 400 milliseconds.
If you do not plan to send or receive faxes on a given voice/fax channel, you can disable faxes in
the Fax group.
12. You can enable the voice/fax advanced features by clicking (checking) the silence compression,
echo cancellation, or forward error correction options.
The Silence Compression option defines whether silence compression is enabled (checked) for
this voice channel. If silence compression is enabled, the MultiVOIP 200 will not transmit voice
packets when silence is detected, thereby reducing the amount of network bandwidth that is
being used by the voice channel.
This Echo Cancellation option defines whether echo cancellation is enabled (checked) for this
voice channel. If echo cancellation is enabled, the MultiVOIP 200 will remove echo-delay which
improves the quality of sound.
The Forward Error Correction (FEC) option defines whether forward error correction is enabled
(checked) for this voice channel. The FEC feature allows some of the voice packets that were
corrupted (or lost) to be recovered. FEC adds an additional 50% overhead to the total network
bandwidth consumed by the voice channel.
Note: After configuring a given channel (1 or 2), you can copy that channel’s configuration by
clicking the Copy button and everything on the Voice/Fax tab will be copied to the other channel.
The Billing/Misc tab displays the parameters for auto call, automatic disconnection, billing
options and dynamic jitter buffer.