Yes, it is possible to have a 2811 with both a WLC integrated with SRST Wireless LAN Controller Functionality-Integrated services routers (Cisco 2800 and 3800 series) provide wireless LAN controller functionality with the Cisco Wireless LAN Controller Network Module. The Integrated wireless LAN Controller network module provides system wide wireless LAN functions, such as creating and enforcing security policies, intrusion prevention, RF management, quality of service (QoS), and mobility.

WLAN and wired IP telephony support with Cisco CallManager Express (CCME) and Survivable Remote Site Telephony (SRST).

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http://www.cisco.com/en/US/prod/collateral/routers/ps5854/product_data_sheet0900aecd8016ef57.html