For the 5508 series, the software image is split into two parts which must both be installed: Base Install Image : The primary software. Supplementary AP Bundle
Release 8.3.150.0 acts as a generational bridge. It supports legacy 802.11n access points like the Aironet 1140, 2600, and 3500 series while simultaneously allowing adoption of early Wave 2 802.11ac APs like the Aironet 1830, 1850, 2800, and 3800 series. This allowed enterprises to selectively upgrade physical workspaces without replacing their core central controllers. air-ct5500-k9-8-3-150-0
Despite its age, the 5508 is remembered for its reliability in "mission-critical" environments. For the 5508 series, the software image is
While 8.3.150.0 is stable, engineers must be aware of specific behavior when using this version: For the 5508 series
Comprehensive Guide to Cisco AIR-CT5500-K9 8.3.150.0 Software Release