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Configuring WLAN Services

Configuring the QoS Policy

SCALANCE WLC711

User Guide, V8.11, 07/2012, C79000-G8976-C260-03 6-37

contradiction to the concepts in the 802.11 standard that allow for data packets to wait their turn to

avoid data collisions. Regular traffic on a wireless network is an asynchronous process in which

data streams are broken up by random intervals.

To reconcile the needs of isochronous data, mechanisms are added to the network that give voice

data traffic or another traffic type priority over all other traffic, and allow for continuous

transmission of data.

To provide better network traffic flow, the SCALANCE WLC711 provides advanced Quality of

Service (QoS) management. These management techniques include:

• WMM (Wi-Fi Multimedia) — Enabled on individual WLAN Services, is a standard that

provides multimedia enhancements that improve the user experience for audio, video, and

voice applications. WMM is part of the 802.11e standard for QoS.

• IP ToS (Type of Service) or DSCP (Diffserv Codepoint) — The ToS/DSCP field in the IP

header of a frame is used to indicate the priority and Quality of Service for each frame.

Adaptive QoS ensures correct priority handling of client payload packets tunneled between

the controller and AP by copying the IP ToS/DSCP setting from client packet to the header of

the encapsulating tunnel packet.

Defining the Service Class

Service class is determined by the combination of the following operations:

• The class of treatment given to a packet. For example, queuing or per hop behavior (PHB).

• The packet marking of the output packets (user traffic and/or transport).

The service class is equivalent to the 802.1D UP (user priority).

Table 6-10 Service Classes

Service class name (number) Priority level

Network Control (7) 7 (highest priority)

Premium (Voice) (6) 6

Platinum (video) (5) 5

Gold (4) 4

Silver (3) 3

Bronze (2) 2

Best Effort (1) 1

Background (0) 0 (lowest priority)

Table 6-11 Relationship Between Service Class and 802.1D UP

SC name SC Value 802.1d UP AC Queue

Network Control 7 7 VO VO or TVO

Premium (voice) 6 6 VO VO or TVO

Platinum (video) 5 5 VI VI

Gold 4 4 VI VI

1 2 ... 228 229 230 231 232 233 234 235 236 237 238 ... 491 492

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