Until 7.3 releases, all Wireless LAN controllers (WLC) ran on a dedicated hardware. For example we have 5500 Series, 2100 Series, 2000 series, WiSM on CAT6500 etc. The virtual wireless LAN controller (vWLC) is software that can run on hardware that is compliant with an industry standard virtualization infrastructure. Virtual wireless LAN controllers provide flexibility for users to select the hardware based on their requirement
For more information on this topic, visit:https://supportforums.cisco.com/docs/DOC-26765?referring_site=YouTube&channel=video
