The Wireless SSID on a mf7811 model AP, bridges to the ISP/Ethernet. Your ISP however, may not provide more than one IP address, so your laptop is likely not getting DHCP. This AP does not do NAT (router) translation, to provide multiple Internet connections over a single ISP address. Ruckus uses a proprietary 4-MAC address WDS for 7111s, not necessarily compatible with other 3rd party devices.
What happens if you connect your laptop to the Eth port of a 7111 CPE instead of your Set-Top Box? The 7811 ships with 3 x 7111 CPEs, if you find them for sale on eBay or other older equipment VAR. Ruckus no longer makes/sells this product.