Network Architecture Design
On a large and midsize campus network, the WLAN typically uses the "WAC + Fit AP" networking architecture. Depending on the location of the WAC, two WAC deployment modes are available: in-path and off-path. When a native WAC (integrated on a switch) is used, only the in-path deployment mode can be adopted. When a standalone WAC is used, the two deployment modes are both supported (off-path mode recommended). Table 1 compares the two deployment modes.
Deployment Mode |
Application Scenario |
Advantage |
Disadvantage |
|---|---|---|---|
In-path mode |
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Off-path mode |
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In centralized forwarding mode is used, much bandwidth of the switch is consumed. |
It is recommended that the standalone WAC be deployed at the core layer.
User data packets on a WLAN can be forwarded in tunnel (centralized) or direct (local) mode, as described in Table 2. Centralized forwarding is recommended on large- and medium-sized campus networks for central traffic management and control.
Forwarding Mode |
Application Scenario |
Advantage |
Disadvantage |
|---|---|---|---|
Centralized forwarding |
The WAC centrally processes and forwards user service data. |
The WAC forwards data packets in centralized manner, ensuring high security and facilitating centralized traffic management and control. |
Service data must be forwarded by the WAC, reducing packet forwarding efficiency and burdening the WAC. |
Local forwarding |
User data is directly forwarded without passing through the WAC, saving AP-WAC link bandwidth. |
Service data does not need to be forwarded by the WAC, improving packet forwarding efficiency and reducing the burden on the WAC. |
Service data is difficult to manage and control in a centralized manner. |