Traffic Shaping

Hi,

I went through the screencast for the VoIP traffic shaper and set it up, however when I was looking for some answers on a slightly different topic I came across something that leads me to believe that there is an error that may prevent it from working as intended.

Basically, http://doc.m0n0.ch/screencasts/traffic-shaping-for-voip.wmv says to set TOS on the inbound and outbound traffic yes to lowdelay and throughput. When I watched the video I thought it meant it would add those flags to the packet, but now I understand that the packet has to have those flags for the rule to apply. And ISP routers do not set those flags, lol, or so I read. http://www.dslreports.com/forum/remark,16651123

The screencast was great and was a great eye opener for a newbie

Can somebody please confirm if the screen cast has an error? I would appreciate it.

Thanks!

Anybody?

Sorry for the delay. I don't drop by here often so didn't see you question until today.

The simple fact is that end-to-end QoS doesn't really exist over an internet connection. As you note, many ISPs simply ignore QoS tags in traffic. Some may even strip them out.

That means that incoming VoIP traffic may not be tagged for high priority. It also means that tagging outgoing traffic may be pointless. This is why QoS provisions alone are not an adequate solution for many people. That is where traffic shaping comes in.

Traffic shaping can be implemented completely without regard for QoS tags. Thus it does not depend upon upstream QoS being honored by your ISP, or any other bandwidth provider along the path of your call.