ZyXEL Communications VMG1312-T10C, User Manual

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Chapter 9 Quality of Service (QoS)
VMG1312-T10C User’s Guide
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CoS technologies includes DiffServ (Differentiated Services 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 79
Network Setting > QoS > General
The following table describes the labels in this screen.
Table 39
Network Setting > QoS > General
LABEL DESCRIPTION
Active QoS Select the check box to turn on QoS to improve your network performance.
You can give priority to traffic that the Device forwards out through the WAN interface.
Give high priority to voice and video to make them run more smoothly. Similarly, give
low priority to many large file downloads so that they do not reduce the quality of other
applications.
Traffic priority will
be automatically
assigned by Select how the Device assigns priorities to various upstream traffic flows.
• None: Disables auto priority mapping and has the Device put packets into the
queues according to your classification rules. Traffic which does not match any of
the classification rules is mapped into the default queue with the lowest priority.
• Ethernet Priority: Automatically assign priority based on the IEEE 802.1p priority
level.
• IP Precedence: Automatically assign priority based on the first three bits of the
TOS field in the IP header.
• Packet Length: Automatically assign priority based on the packet size. Smaller
packets get higher priority since control, signaling, VoIP, internet gaming, or other
real-time packets are usually small while larger packets are usually best effort data
packets like file transfers.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.