Multi-Tech Systems MULTIVOIP MVP210/410/810 - Manual (Page 39)

Chapter 4: Configuring your VOIP
Multi-Tech Systems, Inc. 39
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 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 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
(Not available on the –SS series)
The Configurable Payload Type is located on the bottom of the Voice/Fax screen. 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 will fail. To avoid these failures, the payload types are made configurable.
DTMF RFC2833 Configurable Payload Type is supported only for SIP & SPP and not for H.323.
Whenever you interoperate with older MultiVOIP products (i.e., earlier than release x.11), for backward
compatibility, make sure to configure the payload type values to default ones, which match the values of
older MultiVOIP’s.