Are you using a VPN and/or a security App such as Norton or MacAfee with your iPad? If so, you will likely need to disable or completely remove the VPN profile or security App from your device.
VPNs (and some network proxies) will, by definition, inhibit direct access to local network resources (including AirPrint, AirPlay etc) - unless they are explicitly configured to permit “split tunnelling”. When using a standard VPN, all network traffic is routed to your VPN Providers Gateway - from which your traffic will be delivered to the operator's network and the internet.
Those VPNs that permit (and are so configured) for spit-tunnel allow access to the local network while routing internet traffic via the VPN connection and the VPN provider’s VPN Gateway. Those clients that disallow split-tunnel will inhibit all access to local printers and other local network resources.