Over the last years, Wireless Local Area Networks (WLANs) have been extensively deployed and have significantly evolved. However, the deployment of large-scale WLAN still has management issues. Moreover, while newer WLAN technologies and services have been emerging at a prolific rate, the architecture of WLAN networks has largely been static and difficult to evolve. In this paper, we present a novel architecture for carrier-managed WLAN networks which leverages Network Function Virtualization concepts and virtualization technology in general. It is based on a WLAN Cloudlet which offloads MAC layer processing from access points and consolidates network functions and value-added services. All these functions and services are based on software instances. This brings more flexibility and adaptability and permits to easily implement new services while reducing CAPEX/OPEX and network equipment cost (e.g., access points).