Reliability Design
WLAN reliability includes WAC reliability and AP reliability.
WAC Reliability
In a WAC + Fit AP architecture, a WAC is the control and management center of the entire WLAN. Therefore, the AC's security and reliability are important, and the WAC reliability design must be considered in WLAN construction.
Native WAC reliability depends on the reliability of the device with the native WAC configured. That is, a device can be configured with stacking or multiple links to achieve high reliability. If the native WAC is used, the stacking mode is recommended.
Table 3-9 lists the reliability scheme of the standalone WAC. The two-node hot standby (HSB) mode is recommended.
Backup Mode |
Application Scenario |
Characteristics |
Description |
|---|---|---|---|
Two-node HSB, including dual-link and Virtual Router Redundancy Protocol (VRRP) modes |
Scenarios with high reliability requirements |
|
1. The models and software versions of the active and standby WACs must be the same. 2. This backup mode cannot be configured with CAPWAP tunnel DTLS encryption. 3. VRRP is a Layer 2 protocol and can be deployed only on Layer 2 networks. VRRP HSB supports only the active/standby mode. 4. The WAC cannot be used as the DHCP server for STAs. |
Dual-link cold backup |
Scenarios without relatively low reliability requirements |
|
1. The active and standby WACs can use different models but must use the same software version. 2. The WAC cannot be used as the DHCP server for STAs. |
N+1 cold backup |
Scenarios that have high cost control requirements but no high reliability requirements |
|
The active and standby WACs can be of different models but must use the same software version. |
AP Reliability
AP reliability design focuses on the reliability of network access for STAs to ensure user experience. AP reliability design includes the following aspects:
- Wireless mesh network (WMN): It is a dynamic star-type, self-organizing, self-configuring wireless network made up of multiple wirelessly connected APs organized in a mesh topology. A WMN connects to a wired network through one or more nodes, as shown in the following figure.
Mesh Point (MP): A mesh-capable node that supports automatic topology discovery, automatic route discovery, and data packet forwarding. MPs can provide both mesh service and user access service.
Mesh Portal Point (MPP): An MP that connects the mesh network to other types of networks. The MPP provides the Portal function to allow MPs to communicate with external networks.
The mesh networking function is usually used in outdoor backhaul scenarios. By default, this function is disabled.
- When the wired uplink of an AP is faulty, STAs can connect to neighboring APs in mesh mode, ensuring STA access. In this scenario, the mesh networking function must be enabled.
- When the uplink of an AP is faulty, the SSID can be disabled to enable STAs to access other APs. In this scenario, you are advised to enable the mesh networking function.