Thursday, 27 December 2012

How to use Qos (Quality of Service) on Router

Quality of Service (QoS) is a feature of routers and switches which prioritizes traffic so that more important traffic can pass first. The result is a performance improvement for critical network traffic. QoS equipment is useful with VoIP phones or in LANs with high volumes of local traffic.


The QoS settings can be found under Applications & Gaming -> QoS.
There are many ways to assign priority to your VOIP system.  I just used the IP address as shown below. is the LAN private IP of the Asterisk system.

With the priority of the Asterisk box set to high, we should be all set.  It turns out that unless you cap the bandwidth, you will still have QoS problems.  Enter around 85% of your up and down bandwidth in the Uplink and Downlink boxes.  Capping the bandwidth is required to keep the latency low.  Otherwise, your bandwidth is filled up with large packets and the priority settings are not effective for VOIP traffic.  See for more information.
With the above settings, VOIP calls are now clear even with other concurrent activities.
Several people have reported being able to install dd-wrt on v6 WRT54 routers and the QoS configuration is the same.