User's Manual

Chapter 9 Quality of Service (QoS) 113
QoS versus Cos
QoS is used to prioritize source-to-destination traffic
flows. All packets in the same flow are given
the same priority. CoS (class of service) is a way of managing traffic in a network by grouping similar
types of traffic together and treating each type as a class. You can use CoS to give different priorities
to different packet types.
CoS technologies includes DiffServ (Differentiated S
ervices or DS). DiffServ is a new protocol and
defines a new DS field, which replaces the eight-bit ToS (Type of Service) field in the IP header.
Tagging and Marking
In a QoS class, you can configure whether to add or change the DSCP
(DiffServ Code Point) value ain
a matched packet. When the packet passes through a compatible network, the networking device,
such as a backbone switch, can provide specific treatment or service based on the tag or marker.
9.2 The QoS General Screen
Use this screen to enable or disable QoS, set the bandwidth, and select to have the Device
automatically assign priority to upstream traffic according to the IP precedence or packet length.
Click Network
Setting > QoS to open the General screen.
Figure 74 Network Setting
> QoS > General