Understanding Access Point Clusters

An access point cluster is a dynamic, configuration-aware group of AX411 Access Points in the same subnet of a network. A cluster provides a single point of administration and enables the deployment of access points as a single wireless network instead of a series of separate devices. Each cluster can have up to 16 members. Clusters can share configuration information, such as virtual access point settings and quality-of-service (QoS) queue parameters.

You can manage individual AX411 Access Points through the CLI or J-Web user interface on the SRX Series device. However, you might find it easier to view and configure a group of access points together.

AX411 Access Points must meet the following requirements to participate in a cluster:

Cluster members send periodic advertisements to announce their presence. When a cluster member does not hear these advertisements from a member access point for some duration, the access point is removed from its members list. Access points can be dropped out of a cluster if they lose connectivity to other access points in the cluster.

If an access point loses connectivity to the other access points in the cluster, whether it rejoins the cluster again before it is dropped from the cluster or is dropped from the cluster, any configuration changes during the lost connectivity are propagated to the access point once it resumes its connectivity to the other access points.

Settings Shared Across a Cluster

When a property of a cluster is modified, the configuration change is pushed to all the access points that are members of this cluster. Thus all the cluster members have the same configuration for the shareable properties. The updated configurations are saved implicitly. The following settings are shared across access points in a cluster:

Not all radio settings are shared across a cluster. Only the following radio settings are shared across a cluster:

Settings That Are Not Shared Across a Cluster

Settings that are not shared must be configured individually for each access point.

The following settings are not shared across access points in a cluster:

The following radio settings are not shared across a cluster:

Channel Management in Clustered Access Points

When channel management is enabled for clustered access point, the access point automatically assigns radio channels used by clustered access points to reduce mutual interference (or interference with other access points outside the cluster). Interference can occur when multiple access points within range of each other are broadcasting on the same or overlapping channels. The impact of this interference on network performance can intensify during busy times when a large amount of data and media traffic is competing for bandwidth. Proper channel management maximizes Wi-Fi bandwidth and helps maintain the efficiency of communication over the wireless network. The interference of other radio equipment (such as radar) is not taken into consideration.

Channel management detects the bands (802.11b/g or a or n) the clustered access points are operating on and uses a predetermined collection of channels that will not mutually interfere. The collection of channel is based on the geographic location as guided by the local laws.

Note: Channel management works only when the radio is configured with static channels. It does not work if the radio is set to auto mode.

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