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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
You are mistaking utilization for congestion. At the packet level, a link is congested if it is not immediately available for transmit due to one or more previous packets still being queued/transmitted. This transient congestion causes jitter, VoIP's worst enemy. Certainly, as utilization rises so will congestion; however, it is quite common to have transient congestion while overall utilization is minimal. S ----- Original Message ----- From: "Shawn Solomon" <[email protected]> Sent: Monday, 10 February, 2003 12:54 Subject: RE: VoIP QOS best practices > If you are in an environment where the uplink is already saturated, or > nearly so, QOS is necessary. But QOS only discards packets in times of > contention. So, if you don't have contention, you don't need it. IF > you have 300 people and 4meg of data all fighting for that t1, it makes > a world of difference. > > > - -----Original Message----- > From: Bill Woodcock [mailto:[email protected]]=20 > Sent: Monday, February 10, 2003 1:28 PM > To: Charles Youse > Cc: [email protected] > Subject: RE: VoIP QOS best practices > > > > But I could conceivably have 10+ voice channels over a T-1, I > still > > don't quite understand how, without prioritizing voice traffic, > the > > quality won't degrade... > > Well, of course it all depends how much other traffic you're trying to > get > through simultaneously. Your T1 will carry ~170 simultaneous voice > streams with no conflict, but you have to realize that they'll stomp on > your simultaneous TCP data traffic. But you don't need to protect the > _voice_... > > Look, just do it, and you'll see that there aren't any problems in this > area. > > -Bill > > ------------------------------ > |