Codec Tieline Gateway, User Manual

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© Tieline Research Pty. Ltd. 2021
Gateway and Gateway 4 Manual v1.2
24.9
Configuring the Jitter Buffer
Jitter, (also known as latency or delay), is the amount of time it takes for a packet of data to get
from one point to another. A jitter buffer is a temporary storage buffer used to capture incoming data
packets. It is used in packet-based networks to ensure the continuity of audio streams by
smoothing out packet arrival times during periods of network congestion. Data packets travel
independently and arrival times can vary greatly depending on network congestion and the type of
network used, i.e. LAN versus wireless networks. The concept of jitter buffering is displayed visually
in the following image.
Jitter-buffer management is encompassed within Tieline's SmartStream IP technology which can:
·
Remove duplicate packets.
·
Re-order packets if they arrive out-of-order.
·
Repair the stream in the event of packet loss (error concealment).
·
Manage delay dynamically based on current network congestion.
·
Manage forward error correction (FEC).
With Tieline codecs you can configure either a fixed or automatic jitter buffer and the settings you
use depend on the IP network over which you are connecting. Over LANs, WANs and wireless
networks the automatic jitter buffer generally works well. It adapts automatically to prevailing IP
network conditions to provide continuity of audio streaming and minimize delay.
A fixed jitter buffer is preferable over satellite connections to ensure continuity of signals.
CAUTION: If a Tieline codec connects to a device that is using non-compliant RTP streams
then the last fixed setting programmed into the codec will be enabled (default is 500ms).
Non-compliant devices include some other brands of codec, web streams and other
devices.
Tieline ‘Auto Jitter Buffer’ Settings
The following automatic jitter buffer settings range from the most aggressive "Least Delay" setting,
which endeavors to minimize delay as much as possible while adapting to prevailing network
conditions, to the "Highest Quality" setting, which is the most conservative delay setting to
minimize packet loss when packet latency is not as critical. Best compromise is the most popular
setting used by most broadcasters as it achieves an excellent balance that minimizes latency for
bidirectional communications, as well as minimizing packet loss over most wired and wireless IP
networks.