Fast transition is the correct solution because it refers to IEEE 802.11r Fast BSS Transition, which reduces the authentication delay when a wireless client roams from one AP to another. Cisco describes 802.11r Fast Transition as a feature for seamless wireless roaming and states that, after configuration, the WLAN supports faster client roaming between access points. Cisco’s Catalyst 9800 roaming documentation also identifies 802.11r as the mechanism focused on seamless transition between APs, while 802.11k and 802.11v assist with neighbor reporting and network-assisted roaming decisions.

The core advantage is that key negotiation and authentication preparation occur before or during the roam, reducing the interruption experienced by latency-sensitive applications such as voice, video, collaboration tools, and real-time enterprise applications. Static VLAN policy only controls segmentation and does not accelerate roaming. Optimized roaming can help discourage sticky clients from remaining associated to poor-quality APs, but it is not the primary fast-roam authentication mechanism. A redundant RF profile is not an 802.11 roaming solution. Reference topics:802.11r Fast BSS Transition, client roaming, WLAN mobility behavior, Catalyst 9800 WLAN security, and seamless roaming design.