C Ha Pte R 10 Q Ua Lity O F Se Rvic E (Q O S); Overview; What You Can Do In This Chapter - ZyXEL Communications XMG3512-B10A User Manual

Q ua lity o f Se rvic e (Q o S)
10.1 O ve rvie w
Quality of Service (QoS) refers to both a network's ability to deliver data with minimum delay, and the
networking methods used to control the use of bandwidth. Without QoS, all traffic data is equally likely
to be dropped when the network is congested. This can cause a reduction in network performance and
make the network inadequate for time-critical application such as video-on-demand.
Configure QoS on the XMG to group and prioritize application traffic and fine-tune network
performance. Setting up QoS involves these steps:
1 Configure classifiers to sort traffic into different flows.
2 Assign priority and define actions to be performed for a classified traffic flow.
The XMG assigns each packet a priority and then queues the packet accordingly. Packets assigned a
high priority are processed more quickly than those with low priority if there is congestion, allowing time-
sensitive applications to flow more smoothly. Time-sensitive applications include both those that require
a low level of latency (delay) and a low level of jitter (variations in delay) such as Voice over IP (VoIP) or
Internet gaming, and those for which jitter alone is a problem such as Internet radio or streaming video.
This chapter contains information about configuring QoS and editing classifiers.
10.1.1 Wha t Yo u C a n Do in this C ha pte r
• Use the
G e ne ra l
page 133).
• Use the
Q ue ue Se tup
• Use the
C la ssific a tio n Se tup
• Use the
Sha pe r Se tup
(Section 10.6 on page
• Use the
Po lic e r Se tup
page 142).
screen to enable or disable QoS and set the upstream bandwidth
screen to configure QoS queue assignment
screen to add, edit or delete QoS classifiers
screen to limit outgoing traffic transmission rate on the selected interface
141).
screen to control incoming traffic transmission rate and bursts
XMG3512-B10A User's Guide
131
C
HA PTER
(Section 10.4 on page
(Section 10.5 on page
1 0
(Section 10.3 on
134).
137).
(Section 10.7 on