© Copyright 2018 TRENDnet. All Rights Reserved.
TRENDnet User’s Guide
TPE‐TG82ES
33
QoS (Quality of Service)
When a port on an Ethernet switch becomes oversubscribed, its egress
queues contain more packets than the port can handle in a timely manner. In this
situation, the port may be forced to delay the transmission of some packets, resulting in
the delay of packets reaching their destinations. A port may be forced to delay
transmission of packets while it handles other traffic, and, in some situations, some
packets destined to be forwarded to an oversubscribed port from other switch ports
may be discarded.
Minor delays are often of no consequence to a network or its performance. But there
are applications, referred to as delay or time sensitive applications, which can be
impacted by packet delays. Voice transmission and video conferences are two examples.
If packets carrying data in either of these cases are delayed from reaching their
destination, the audio or video quality may suffer.
This is where Cost of Service (CoS) is of value. It allows you to manage the flow of traffic
through a switch by having the switch ports give higher priority to some packets, such as
delay sensitive traffic, over other packets. This is referred to as prioritizing traffic.
Set CoS priority settings
QoS > CoS
1. Log into your switch management page (see “
Access your switch management page
”
on page 6).
2. Click on
QoS
and click on
CoS
.
3. In
QoS Status
, select
Enabled
and then click
Apply
.
4. In the left hand panel, click on
Save
5. Click
Save Settings to Flash
, then click
OK
Note:
This step saves all configuration changes to the NV‐RAM to ensure that if the
switch is rebooted or power cycled, the configuration changes will still be applied.
Set Port Priority
QoS > Port Priority
The Port Priority values are assigned to an untagged frame at ingress for internal
processing in the switch. This procedure explains how to change the default mappings of
port priorities to the User Priority. This is set at the switch level. You cannot set this at
the per‐port level. To change the port priority mappings, perform the following
procedure.
1. Log into your switch management page (see “
Access your switch management page
”
on page 6).
2. Click on
QoS
and click on
Port Priority
.
3.
For each port whose priority you want to change, select a priority (Low‐Highest) in
the
User Priority
column. Click
Apply
to save the settings.
4. In the left hand panel, click on
Save