User guide

Chapter 4 – Configuring Your MultiVOIP
42 MultiVOIP® Voice/Fax over IP Gateways
Voice/Fax Parameter Definitions (continued)
Field Name
Values
Description
Dynamic Jitter
Dynamic Jitter Buffer
Dynamic 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 affects the voice delay between MultiVOIP gateways.
Minimum Jitter Value
60 to 400
ms
The minimum dynamic jitter buffer of 60 milliseconds is the minimum delay that
would be acceptable over a low jitter network.
Default = 150 ms
Maximum Jitter Value
60 to 400
ms
The maximum dynamic jitter buffer of 400 milliseconds is the maximum delay
tolerable over a high jitter network.
Default = 300 ms
Optimization Factor
0 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.
Auto Disconnect
Automatic
Disconnection
--
The Automatic Disconnection group provides four options which can be used singly
or in any combination.
Jitter Value
1-65535
The 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 is 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 Duration
1-65535
Call 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 some configurations, requiring upward adjustment.
Consecutive Packets
Lost
1-65535
Consecutive 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 Disconnection
1 to 65535;
Default =
30 sec.
Specifies how long to wait before disconnecting the call when IP network connectivity
with the remote site has been lost.
Configurable Payload Type
The Configurable Payload Type is not available on the –SS series.
The Configurable Payload Type is located on the bottom of the Voice/Fax window. The Configurable Payload
Type is used when the remote side uses a different payload type for the associated features. In previous
firmware versions, MultiVOIP’s used 101 for DTMF RFC2833. If the remote side uses some other dynamic
payload type such as 110, it fails. To avoid these failures, the payload types are configurable.
DTMF RFC2833 Configurable Payload Type is supported only for SIP & SPP and not for H.323.