Multi-Tech Systems Mvp-2400/2410/3010, Mvp-210/410/810 Voice/ip Gateways User Guide

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The Voice/FAX Parameters fields are described in the tables below.
Voice/Fax Parameter Definitions
Field Name Values Description
Default -- When this button is clicked, all
Voice/FAX parameters are set to their
default values.
Select
Channel1-2 (210)
1-4 (410)
1-8 (810)Channel to be configured is selected
here.
Copy
Channel-- Copies the Voice/FAX attributes of
one channel to another channel.
Attributes can be copied to multiple
channels or all channels at once.
Voice Gain -- Signal amplification (or attenuation)
in dB.
Input Gain +31dB
to
 –31dBModifies audio level entering voice
channel before it is sent over the
network to the remote VOIP. The
default & recommended value is 0 dB.
Output Gain +31dB
to
 –31dBModifies audio level being output to
the device attached to the voice
channel.  The default and
recommended value is 0 dB.
DTMF Parameters
DTMF Gain -- The DTMF Gain (Dual Tone Multi-
Frequency) controls the volume level
of the digital tones sent out for Touch-
Tone dialing.
DTMF Gain,
High Tones+3dB to
-31dB &
“mute”Default value:  -4 dB.  Not to be
changed except under supervision of
MultiTech’s Technical Support.
DTMF Gain,
Low Tones+3dB to
-31dB &
“mute”Default value:  -7 dB.  Not to be
changed except under supervision of
MultiTech’s Technical Support. 
						

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Voice/Fax Parameter Definitions (cont’d)
Field Name Values Description
DTMF Parameters
Duration
(DTMF)60 – 3000
msWhen DTMF: Out of Band is
selected, this setting determines
how long each DTMF digit ‘sounds’
or is held.  Default = 100 ms.
DTMF
In/Out of
BandOut of
Band, or
InbandWhen DTMF Out of Band is
selected (checked), the MultiVOIP
detects DTMF tones at its input and
regenerates them at its output.
When DTMF Inband is selected,
the DTMF digits are passed through
the MultiVOIP unit as they are
received.
FAX Parameters
Fax Enable    Y/NEnables or disables fax capability for a
particular channel.
Max Baud
Rate
(Fax)2400, 4800,
7200, 9600,
12000,
14400 bpsSet to match baud rate of fax machine
connected to channel (see Fax machine’s
user manual).
Default = 14400 bps.  
Fax Volume
(
Default =
-9.5 dB
 )
-18.5 dB
to –3.5 dBControls output level of fax tones.  To
be changed only under the direction of
Multi-Tech’s Technical Support.  
Jitter Value
(Fax)Default =
400 msDefines the inter-arrival packet
deviation (in milliseconds) for the fax
transmission. A higher value will
increase the delay, allowing a higher
percentage of packets to be
reassembled.  A lower value will
decrease the delay allowing fewer
packets to be reassembled.
Mode (Fax) FRF 11;
T.38
(T.38 not
currently
sup-
ported)FRF11 is frame-relay FAX standard
using these coders: G.711, G.728, G.729,
G.723.1.
T.38 is an ITU-T standard for storing
and forwarding FAXes via email using
X.25 packets.  It uses T.30 fax standards
and includes special provisions to
preclude FAX timeouts during IP
transmissions.   
						

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Voice/Fax Parameter Definitions (cont’d)
Coder Parameters
Coder
Manual or
Auto-
maticDetermines whether selection of
coder is manual or automatic.
When Automatic is selected, the
local and remote voice channels will
negotiate the voice coder to be used
by selecting the highest bandwidth
coder supported by both sides
without exceeding the Max
Bandwidth setting.  G.723, G.729, or
G.711 are negotiated.
Selected
CoderG.711 a/u
law 64
kbps;
G.726, @
16/24/32
/40 kbps;
G.727, @
nine bps
rates;
G.723.1 @
5.3 kbps,
6.3 kbps;
G.729,
8kbps;
Net Coder
@
6.4, 7.2, 8,
8.8, 9.6
kbpsSelect from a range of coders with
specific bandwidths. The higher the
bps rate, the more bandwidth is
used. The channel that you are
calling must have the same voice
coder selected.
Default = G.723.1 @ 6.3 kbps, as
required for H.323.   Here 64K of
digital voice is compressed to 6.3K,
allowing several simultaneous
conversations over the same
bandwidth that would otherwise
carry only one.
To make selections from the
Selected Coder drop-down list, the
Manual option must be enabled.
Max
bandwidth
(coder)11 – 128
kbpsThis drop-down list enables you to
select the maximum bandwidth
allowed for this channel.  The Max
Bandwidth drop-down list is
enabled only if the Coder is set to
Automatic.
If coder is to be  selected
automatically (“Auto” setting), then
enter a value for maximum
bandwidth. 
						

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Voice/Fax Parameter Definitions (cont’d)
Field Name Values Description
Advanced Features
Silence
Compression
Y/NDetermines whether silence
compression is enabled (checked) for
this voice channel.
With Silence Compression enabled, the
MultiVOIP will not transmit voice
packets when silence is detected,
thereby reducing the amount of
network bandwidth that is being used
by the voice channel.
Default = off.
Echo
CancellationY/NDetermines whether echo cancellation is
enabled (checked) for this voice
channel.
Echo Cancellation removes echo and
improves sound quality.  Default = on.
Forward
Error
CorrectionY/NDetermines whether forward error
correction is enabled (checked) for this
voice channel.
Forward Error Correction enables
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.             Default = Off
Auto Call
EnableY/NThe Auto Call option enables the local
MultiVOIP to call a remote MultiVOIP
without the user having to dial a Phone
Directory Database number. As soon as
you access the local MultiVOIP
voice/fax channel, the MultiVOIP
immediately connects to the remote
MultiVOIP identified in the Phone
Number box of this option.
Phone No.
(Auto Call)--Phone number used for Auto Call
function.  A corresponding phone
number must be listed in the Outbound
Phonebook. 
						

							MultiVOIP User Guide Technical Configuration (Analog)
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Voice/Fax Parameter Definitions (cont’d) )
Field Name Values Description
Dynamic Jitter
Dynamic
Jitter BufferDynamic Jitter defines a minimum
and a maximum jitter value for
voice communications. When
receiving voice packets from a
remote 
MultiVOIP, varying delays
between packets may occur due to
network traffic problems. This is
called Jitter. To compensate, the
MultiVOIP  uses a Dynamic Jitter
Buffer.  The Jitter Buffer enables the
MultiVOIP to wait for delayed
voice packets by automatically
adjusting the length of the Jitter
Buffer between configurable
minimum and maximum values.
An Optimization Factor adjustment
controls how quickly the length of
the Jitter Buffer is increased when
jitter increases on the network. The
length of the jitter buffer directly
effects the voice delay between
MultiVOIP gateways.
Minimum
Jitter Value60 to 400
msThe minimum dynamic jitter buffer
of 60 milliseconds is the minimum
delay that would be acceptable over
a low jitter network.
Default = 150 msec 
						

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Voice/Fax Parameter Definitions (cont’d)
Field Name Values Description
Dynamic Jitter
Maximum
Jitter Value60 to 400
msThe maximum dynamic jitter buffer
of 400 milliseconds is the maximum
delay tolerable over a high jitter
network.
Default = 300 msec
Optimizat-
ion Factor0 to 12 The Optimization Factor
determines how quickly the length
of the Dynamic Jitter Buffer is
changed based on actual jitter
encountered on the network.
Selecting the minimum value of 0
means low voice delay is desired,
but increases the possibility of jitter-
induced voice quality problems.
Selecting the maximum value of 12
means highest voice quality under
jitter conditions is desired at the
cost of increased voice delay.
Default = 7. 
						

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Voice/Fax Parameter Definitions (cont’d) )  
Field Name Values Description
Auto Disconnect
Automatic
Disconnect-
ion-- The Automatic Disconnection
group provides four options which
can be used singly or in any
combination.
Jitter Value 1-65535
milli-
secondsThe Jitter Value defines the average
inter-arrival packet deviation (in
milliseconds) before the call is
automatically disconnected. The
default is 300 milliseconds. A higher
value means voice transmission will
be more accepting of jitter. A lower
value is less tolerant of jitter.
Inactive by default. When active,
default = 300 ms.  However, value
must equal or exceed Dynamic
Minimum Jitter Value.
Call
Duration1-65535
secondsCall Duration defines the
maximum length of time (in
seconds) that a call remains
connected before the call is
automatically disconnected.
Inactive by default.
When active, default = 180 sec.
This may be too short for most
configurations, requiring upward
adjustment.
Consecutive
Packets Lost1-65535Consecutive Packets Lost defines
the number of consecutive packets
that are lost after which the call is
automatically disconnected.
Inactive by default.
When active, default = 30
Network
Discon-
nection1 to 65535
seconds;
Default =
30 sec.Specifies how long to wait before
disconnecting the call when IP
network connectivity with the
remote site has been lost. 
						

							MultiVOIP User Guide Technical Configuration (Analog)
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9. Set Telephony Interface Parameters.  This dialog box can be reached
by pulldown menu, toolbar icon, keyboard shortcut, or sidebar.
Accessing Telephony Interface Parameters
Pulldown Icon
Shortcut Sidebar
     Ctrl + I 
						

							MultiVOIP User Guide Technical Configuration (Analog)
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In each field, enter the values that fit  your particular network.
The kinds of parameters for which values must be chosen depend on
the type of telephony supervisory signaling or interface used (FXO,
E&M, etc.).  We present here the various parameters grouped and
organized by interface type. 
						

							MultiVOIP User Guide Technical Configuration (Analog)
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FXS Loop Start Parameters.  The parameters applicable to FXS Loop
Start are shown in the figure below and described in the table that
follows.
FXS Loop Start Interface: Parameter Definitions
Field Name Values Description
FXS Loop Start Y/N Enables FXS Loop Start
interface type.  
Inter Digit
Timerinteger values
in secondsThis is the length of time that
the MultiVOIP will wait
between digits.  When the time
expires, the MultiVOIP will
look in the phonebook for the
number entered.
Default = 2.