Level of latency and jitter

f.campos · ‎08-03-2001

Hi,

I would be grateful if anyone could tell me the maximum level of latency and jitter in a network IP that can be supported by a videoconference system H323.

The system is comprised of terminals Picturetel, Polycom, MCU and gateway Cisco.

mmellet · ‎08-09-2001

I would guess latency somewhere around 70 milliseconds. Has anyone seen a definite number? I know it’s low.

maxiaojia · ‎08-10-2001

One book from Cisco is saying better less than 125 msec, no more than 150 msec (round-trip)for interactive real-time video or audio. But I think it is only a recommendation, which level you would like to use is really depends on your clients' expectation for video and audio quality...

pcallahan · ‎08-16-2001

I agree with maxiaojia. Under 150msec is the benchmark you are looking to achieve. I may be working a project like this in the near future and would like to know what your outcome is.

hburgos · ‎08-16-2001

150 msec round trip ? I keep getting conflicting information on this.. I've read 150 msec one way.

Which is it ? one way or round trip ?

sachon · ‎08-17-2001

The ITU recommends no more than 150ms round trip

f.campos · ‎08-17-2001

Round Trip or One-Way?

According this URL is 150 ms one way...

http://www.cisco.com/univercd/cc/td/doc/product/voice/ip_tele/avvidqos/qosintro.htm#xtocid80814

cagboh · ‎09-09-2001

ITU-T's G.114 Specification recommends 150sec ONE-WAY delay; mouth to ear for real-time applications, however, video applications are less sensitive to delay with respect to voice.

BR,

Charles - Ebone

paul-crawford · ‎09-26-2001

It's great to finally find some answers to this question, but just to be totally clear about this (if possible)...

Here:

Networked Multimedia Overview

http://www.cisco.com/warp/public/614/19.html under latency it says that it has to be under 400ms. Is this just the maximum latency that the call can have while still maintaining a connection, and that and delay under 150ms means that the delay/latency won't be a factor in the overall quality?

As well, what is the recommended/minimum/maximum jitter...

or are all of these questions too product specific?

Thanks

zabriskis · ‎10-25-2001

For a discussion on this see the white paper iPower Reliability and IP Precendence, it is on the last couple of pages at http://www.picturetel.com/integrated.asp?name=intwp.xml

The PictureTel Jitter buffer is set to 150ms, whereas the Polycom is at 75ms.