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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: VoIP QOS best practices
On Mon, 10 Feb 2003, Leo Bicknell wrote: > In a message written on Mon, Feb 10, 2003 at 01:19:08PM -0500, chaim fried wrote: > > happens). There is no reason to implement QOS on the Core. Having said > > that, there still seems to be too many issues on the tier 1 networks > > with pacekt reordering as they affect h.261/h.263 traffic. <snip> > So what's the real problem here? Are the VOIP boxes unable to > handle out of order packets? Do the out of order packets simply > arrive far enough delayed to blow the delay budget? What percentage of > reordered packets starts to cause issues? You have two choices Drop them - you either have gaps in the stream or the codec allows for gaps and reconsutrcts small missing sections (buffer to do this) Reorder them - fine, but you need to buffer, we want to minimise delay so how long do you want to wait, what delay is acceptable on top of the other delays we have as well.. (same outcome as jitter) As to what percentage is a problem, that depends on which of the two above ways you are using and how much delay you want. Or in the drop it scenario how many missing frames cause the speech to become degraded. Steve
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