The Cisco Aironet 4800 Series Access Point is a tri-radio, high-performance access point designed for high-density environments. It draws significantly more power than older dual-radio APs and requires IEEE 802.3bt (also known as PoE++), which provides up to 90W per port at the Power Sourcing Equipment. IEEE 802.3af (Type 1 PoE) delivers only 15.4W and 802.3at (Type 2 PoE+) provides up to 30W — both are insufficient for full functionality of the 4800 series, which has a dedicated third scanning radio that requires the additional power budget provided by 802.3bt. IEEE 802.3ac is a standard related to VLAN tagging and is entirely unrelated to Power over Ethernet. Engineers designing wired infrastructure for Cisco 4800 deployments must ensure switches support 802.3bt Type 3 or Type 4 to guarantee full AP functionality across all three radios simultaneously. Reference: WLSD Study Guide — Wired Infrastructure Design, PoE Standards and Power Budget Planning, Cisco 4800 Series AP Specifications.