802.11k allows the WLAN system to access client wireless resources

The IEEE 802.11 WLAN standard allows access points and switches of different vendors to communicate with each other, but it does not allow the WLAN system to access the wireless resources of the client. This defect limits the ability of management institutions to effectively manage their networks. Therefore, IEEE has established a working group to develop a new standard, namely, 802.11k wireless resource management RRM. This standard improves the detection of wireless access points, client operations, and environmental data, thus improving the WLAN operation and management efficiency.

Load Balancing

802.11k focuses on two key elements of WLAN, namely the Access Point AP) and the client. It aims to enable the layer and Layer 2 of the OSI protocol stack, that is, the measurement data at the physical layer and data link layer can be used on the upper layer. This means that the previous layer can make decisions on the wireless environment and determine the measurements needed in that wireless environment. An important feature of this standard is to better allocate the business volume.

Generally, wireless devices connect to the access point with the strongest transmit signal, which overload some access points and some access points with insufficient load, thus reducing the overall service quality. 802.11k will enable the network management software to detect this situation and connect the user end to the unutilized access point. Although those access points have weak signals, they can provide large throughput. In this way, you can connect to the user end of the original Access Point and connect other users to the unutilized access point to achieve a higher connection speed. For the user end, 802.11k aims to provide critical client feedback to WLAN Access Points and switches. Its role is to enhance the capability of 802.11 standard wireless resource management. The standard defines a series of measurement requests and layer-1 and layer-2 client detailed statistical reports. In most cases, the Access Point or WLAN switch requires the client to report data, but sometimes the client can also request data from the Access Point. Because 802.11k is designed to be implemented in software, the existing WLAN devices can support this standard after being upgraded.

Rich management functions

The functions implemented by 802.11k include roaming decision making, RF channel knowledge, channel load, hidden nodes, client statistics, beacon, histogram, and transmission power control TPC.

To improve roaming decisions, access points or WLAN switches provide site reports to clients. The standard first defines a beacon request. According to the beacon request, the access point requires the client to access a specific channel and reports all access point signals it hears. The Access Point collects data, and the Access Point or WLAN switch analyzes the beacon information to check the detailed requirements, such as what type of service and encryption is supported by each access point, and how the client listens to the beacon signal strength of the Access Point. Then, the vswitch or access point generates an access point sequence table from the best to the worst service. This sequence table is called a site report.

Currently, access points and clients cannot share channel information. When 802.11k is used, the access point creates a "noise histogram" for the client, which displays all non-802.11 energy on the client channel. The access point can also request the channel load or use the channel length within the specified time. Then, the Access Point or WLAN switch will know whether the interference or information on a channel is too large, so as to determine whether it can be provided to WLAN communication.

A hidden node is a client or access point that other clients or access points cannot hear. In section 802.11, to avoid conflicts, the node listens before radio waves are launched. When hidden nodes appear, multiple nodes can be simultaneously transmitted, resulting in interference, reducing the performance of WLAN. After 802.11k is used, the client tracks hidden nodes, and the Access Point queries clients relative to hidden nodes. This query information reports the client at the network edge to the access point. The Access Point uses this information to direct the client to an access point that can provide better services for them.

802.11 client statistics, limited to statistics on access points or WLAN switch maintenance. The current WLAN tracking items include packet calculation, packet statistics sent and received. When 802.11k is used, access points and WLAN switches can query all clients to obtain their statistical reports. Based on the Data queried by access points and switches, the WLAN system provides a more complete view of network performance.

Expand TPC applications

In the past, TPC was defined in 802.11h to meet the frequency management requirements in the 5 GHz band. When 802.11k is used, TPC applications are extended to other management areas and frequency bands to reduce interference and power consumption, and control the propagation range of radio waves. It helps network administrators establish a better WLAN. the improvement of Radio Wave Propagation control is conducive to network management and ensures reliable network access even when roaming. At the same time, due to the improvement of WLAN utilization, service efficiency is also higher.

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