I recently setup a new Cisco 887W wireless router which caused me some initial confusion when I got to the wireless config stages. Unlike the Cisco 877W’s I have setup in the past the newer 887W is setup slightly differently. It’s best to think of the Cisco 887W as two routers inside one box, with a hidden ethernet cable linking them. The normal router and the wireless router are completely separate and they both have their own IOS.
To configure the wireless AP part of the router you need to first login to normal wired router IOS and then connect to the wireless AP IOS with the following command:
service-module wlan-ap0 session