Quality Of Service - Draytek Vigor2910 Series User Manual

Default TX limit
Default RX limit
Limitation List
Start IP
End IP
Each/Shared
TX limit
RX limit
Add
Edit
Delete
Index (1-15) in Schedule
Setup
3 . 7 . 3 Q u a l i t y
3 . 7 . 3 Q u a l i t y
Deploying QoS (Quality of Service) management to guarantee that all applications receive
the service levels required and sufficient bandwidth to meet performance expectations is
indeed one important aspect of modern enterprise network.
One reason for QoS is that numerous TCP-based applications tend to continually increase
their transmission rate and consume all available bandwidth, which is called TCP slow start.
If other applications are not protected by QoS, it will detract much from their performance in
the overcrowded network. This is especially essential to those are low tolerant of loss, delay
or jitter (delay variation).
Another reason is due to congestions at network intersections where speeds of
interconnected circuits mismatch or traffic aggregates, packets will queue up and traffic can
be throttled back to a lower speed. If there's no defined priority to specify which packets
should be discarded (or in another term "dropped") from an overflowing queue, packets of
sensitive applications mentioned above might be the ones to drop off. How this will affect
application performance?
There are two components within Primary configuration of QoS deployment:
Classification: Identifying low-latency or crucial applications and marking them for
high-priority service level enforcement throughout the network.
Vigor2910 Series User's Guide
Define the default speed of the upstream for each computer in
LAN.
Define the default speed of the downstream for each computer
in LAN.
Display a list of specific limitations that you set on this web
page.
Define the start IP address for limit bandwidth.
Define the end IP address for limit bandwidth.
Select Each to make each IP within the range of Start IP and
End IP having the same speed defined in TX limit and RX
limit fields; select Shared to make all the IPs within the range
of Start IP and End IP share the total bandwidth of TX limit
and RX limit.
Define the limitation for the speed of the upstream. If you do
not set the limit in this field, the system will use the default
speed for the specific limitation you set for each index.
Define the limitation for the speed of the downstream. If you
do not set the limit in this field, the system will use the default
speed for the specific limitation you set for each index.
Add the specific speed limitation onto the list above.
Allows you to edit the settings for the selected limitation.
Remove the selected settings existing on the limitation list.
You can type in four sets of time schedule for your request.
All the schedules can be set previously in Application –
Schedule web page and you can use the number that you
have set in that web page.
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