The statement is true as a WLAN design recommendation. Inter-WAC roaming is supported, but it introduces more control-plane interaction and forwarding complexity than intra-WAC roaming. The Home WAC and Foreign WAC must belong to the same mobility group, synchronize station and AP information, and establish an inter-WAC CAPWAP tunnel for control information and, in some scenarios, service forwarding.
Additional synchronization, tunnel processing, route handling, and failure dependencies can increase roaming delay and complicate troubleshooting. This is especially relevant for delay-sensitive applications such as voice, video, automated guided vehicles, and real-time production systems. A better design places APs between which users frequently move under the same WAC wherever controller capacity and physical topology permit.
Avoiding inter-WAC roaming does not mean disabling the function entirely. Large campuses may require multiple WACs for scale, redundancy, or geographic distribution. Mobility groups should still be configured for unavoidable cross-controller movement. However, buildings, floors, and continuous roaming areas should be assigned carefully so that normal roaming remains intra-WAC. Therefore, the recommendation in the statement is correct, and the answer is True.
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