Overview of WLAN QoS

Definition

WLAN Quality of Service (QoS) provides wireless users with differentiated services to satisfy their traffic requirements. WLAN QoS has the following functions:

1. High-efficiency use of wireless channels: The Wi-Fi multimedia (WMM) standard enables high-priority users to preempt wireless channels.
2. Efficient bandwidth use: Priority mapping preferentially transmits the data of high-priority users.
3. Network congestion prevention: Traffic policing limits users' transmission rate, preventing network congestion.
4. Fairness in wireless channel usage: Airtime scheduling assigns users on the same radio with equal channel occupation time.
5. Differentiated service (DiffServ) for different types of packets: Packets of the same type are identified by matching packet information with ACLs. The same QoS policy is provided for packets of the same type to achieve DiffServ for different types of packets.

Purpose

Applications have differentiated network requirements. The traditional WLAN is typically used to transmit data due to its low transmission rate. With the development of new WLAN technologies, WLANs have been applied to media, financial, education, and enterprise networks. In addition to data traffic, WLANs also transmit delay-sensitive multimedia data, such as voice and video. By enforcing QoS policies on a WLAN, the network administrator can properly plan and assign network resources based on service characteristics. The WLAN then provides differentiated access services for applications, meeting customer requirements and improving network use efficiency.