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Cisco Aironet 1100 Series Access Point Installation and Configuration Guide
OL-2851-01
Chapter 13 Configuring QoS
Configuring QoS
Figure 13-1 Upstream and Downstream Traffic Flow
•
The radio downstream flow is traffic transmitted out the access point radio to a wireless client
device. This traffic is the main focus for QoS on a wireless LAN.
•
The radio upstream flow is traffic transmitted out the wireless client device to the access point. QoS
for wireless LANs does not affect this traffic.
•
The Ethernet downstream flow is traffic sent from a switch or a router to the Ethernet port on the
access point. If QoS is enabled on the switch or router, the switch or router might prioritize and
rate-limit traffic to the access point.
•
The Ethernet upstream flow is traffic sent from the access point Ethernet port to a switch or router
on the wired LAN. The access point does not prioritize traffic that it sends to the wired LAN based
on traffic classification.
Precedence of QoS Settings
When you enable QoS, the access point queues packets based on the L2 class of service value for each
packet. The access point applies QoS policies in this order:
1.
Packets already classified—When the access point receives packets from a QoS-enabled switch or
router that has already classified the packets with non-zero 802.1Q/P user_priority values, the access
point uses that classification and does not apply other QoS policy rules to the packets. An existing
classification takes precedence over all other policies on the access point.
2.
QoS Element for Wireless Phones
setting—If you enable the
QoS Element for Wireless Phones
setting, traffic from voice clients takes priority over other traffic regardless of other policy settings.
The
QoS Element for Wireless Phones
setting takes precedence over other policies, second only to
previously assigned packet classifications.
3.
Policies you create on the access point—QoS Policies that you create and apply to VLANs or to the
access point interfaces are third in precedence after previously classified packets and the
QoS
Element for Wireless Phones
setting.
4.
Default classification for all packets on VLAN—If you set a default classification for all packets on
a VLAN, that policy is fourth in the precedence list.
Configuring QoS
QoS is disabled by default. This section describes how to configure QoS on your access point. It contains
this configuration information:
•
Configuration Guidelines, page 13-4
•
Configuring QoS Using the Web-Browser Interface, page 13-4
•
Adjusting Radio Traffic Class Definitions, page 13-8
Radio
downstream
Ethernet
downstream
Wired
LAN
Ethernet
upstream
Radio
upstream
Client
device
Access
point
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