Typical Latency Values; Network Impact On Latency; Impact Of Additional Features On Latency - Digigram IQOYA TALK User Manual

APPENDIX B

Typical Latency Values

The latency you encounter for a connection between an IQOYA TALK and another IP codec depends on the audio
format chosen, the network and the functionalities that the devices provide - and use.
See the table below for maximum latency values in a half-duplex configuration, without failover mechanism or
FEC, with the buffer size set to 0, on an optimized network.
Audio type
PCM
MPEG
AAC-LC
AAL-LC + SBR
AAC-LC +SBR + PS
AAC-LD
AAC-ELD
All measurements were made on stereo samples at 48 kHz.

Network impact on latency

A basic principle: the more your network/architecture components are of quality, the less latency you will
encounter – nevertheless.
In case your network presents disturbances, IQOYA TALK allows you to:
- Absorb the network jitter by choosing an appropriate buffer size
Choose a FEC scheme to make your stream resilient to packet loss with the AAC option, choose an AAC with
-
error resilience (making the coding itself more robust against errors).
However, keep in mind that each of these features will increase the overall latency of your link: The more features
you need to apply here and there to compensate for the suboptimal operation of a link in the chain, the more
processing and / or tape resources you need to use. This makes it not really efficient in terms of latency...

Impact of additional features on latency.

Basic principle: the more functionality you add, the less room you have for optimizing latency.
Having said all of this, here is the best scenario for low latency:
Half-duplex link without any fail-over!
-
- In full-duplex, the latency will be slightly increased.
Audio formats
24 bits
256 kbps
128 kbps
96 kbps
48 kbps
160 kbps
160 kbps
Portable IP audio codec
Latency
26 ms
76 ms
100 ms
220 ms
246 ms
56 ms
48 ms
IQOYA TALK
Description
Layer II
Aka HEv1
Aka HEv2
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