nanog mailing list archives
RE: VoIP QOS best practices
From: "Charles Youse" <cyouse () register com>
Date: Mon, 10 Feb 2003 17:32:51 -0500
But in order for RTP to resync the out-of-order packets it must introduce some delay, no? And that delay causes issues. C. -----Original Message----- From: Stephen Sprunk [mailto:stephen () sprunk org] Sent: Monday, February 10, 2003 5:21 PM To: Leo Bicknell Cc: North American Noise and Off-topic Gripes Subject: Re: VoIP QOS best practices Reordering per se doesn't affect VoIP at all since RTP has an inherent resync mechanism. Reordering is also unlikely, since each packet is sent 20ms or more apart; I'm not aware of any network devices that reorder on that scale. S ----- Original Message ----- From: "Leo Bicknell" <bicknell () ufp org> Sent: Monday, 10 February, 2003 12:43 Subject: Re: VoIP QOS best practices
- --OXfL5xGRrasGEqWY Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 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.=20I've got a question about this issue. Many networks reorder packets for a number of reasons. At least once before I've attempted to measure the effects of this reordering on a number of forms of traffic, but I have never understood the particular effects on VOIP traffic. Indeed, the two times I was asked to investigate this for video people it turns out the video receivers /had no ability to handle out of order frames/. That's right, get one packet out of order and the video stream goes away until it resynchronizes. Now, I realize reordering should not happen to a large percentage of the packets out there, but it also seems to me any IP application has to handle reordering or it's not really doing IP. 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? - --=20 Leo Bicknell - bicknell () ufp org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/ Read TMBG List - tmbg-list-request () tmbg org, www.tmbg.org - --OXfL5xGRrasGEqWY Content-Type: application/pgp-signature Content-Disposition: inline - -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (FreeBSD) Comment: For info see http://www.gnupg.org iD8DBQE+R/LkNh6mMG5yMTYRAsn4AJ9Y1vO1RILDjvGdTJUPmiiknUlpHgCfedQm rOH5KvKO+PVnSVoLPZkG4zI= =LCXI - -----END PGP SIGNATURE----- - --OXfL5xGRrasGEqWY-- ------------------------------
Current thread:
- Re: VoIP QOS best practices, (continued)
- Re: VoIP QOS best practices Kurt Erik Lindqvist (Feb 10)
- RE: VoIP QOS best practices Shawn Solomon (Feb 10)
- RE: VoIP QOS best practices Ray Burkholder (Feb 10)
- RE: VoIP QOS best practices Spencer . Wood (Feb 10)
- RE: VoIP QOS best practices Ray Burkholder (Feb 10)
- RE: VoIP QOS best practices Ray Burkholder (Feb 10)
- Re: VoIP QOS best practices Stephen Sprunk (Feb 10)
- Re: VoIP QOS best practices Stephen Sprunk (Feb 10)
- Re: VoIP QOS best practices Petri Helenius (Feb 10)
- Re: VoIP QOS best practices Stephen J. Wilcox (Feb 10)
- Re: VoIP QOS best practices Petri Helenius (Feb 10)
- RE: VoIP QOS best practices Charles Youse (Feb 10)
- Re: VoIP QOS best practices Stephen Sprunk (Feb 10)
- Re: VoIP QOS best practices Stephen Sprunk (Feb 10)
- Re: VoIP QOS best practices Eric Gauthier (Feb 11)
- Re: VoIP QOS best practices Stephen Sprunk (Feb 10)