Both latency and jitter required for media profiles

[David-P-B]

Feedback

The profile tables on page 12 specifiy a latency but no jitter / network delay variation.
Real time services over IP are typically specified in terms of latency and jitter (or delay variation), e.g as in ITU-T Y.1541.
Delay variation requires buffering in the deocder, increasing the overall latency.

Suggested way forward

For Audio profiles a jitter or delay variation should be specified.
For Video profiles, either:

1. Specify in Note1 explicitly that the latency includes any buffering for delay variation.
2. Separate out the latency into encode + network + encode and specifiy delay variation (harder to specify and probably too implementation specific)

Additional context

If specifying jitter, this should be a max value (not average) and ideally it should be stated as +/- value (relative to the latency).
[5GMAG_REP_01] [CPT_0046.5G]

[tbiat]

Review during 14/12/22 CPT meeting

• CPT46 considers overall latency including jitter.
• Different latency measurement for audio and video. Need to shift the example in annex C as a note for audio profile, and harmonize the wording / referencing.