Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Level of latency and jitter

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.

9 REPLIES
New Member

Re: Level of latency and jitter

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

New Member

Re: Level of latency and jitter

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...

New Member

Re: Level of latency and jitter

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.

New Member

Re: Level of latency and jitter

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 ?

New Member

Re: Level of latency and jitter

The ITU recommends no more than 150ms round trip

New Member

Re: Level of latency and jitter

New Member

Re: Level of latency and jitter

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

New Member

Re: Level of latency and jitter

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

New Member

Re: Level of latency and jitter

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.

418
Views
0
Helpful
9
Replies