You can have a LAP 1242 on the opposite end of a wireless backbone, either running in H-REAP or Local, depending on the bandwidth of the backbone. There are minimum requirements for H-REAP ap's.
For H-REAP's connected to a centralized wireless LAN controller, the WAN link must support a minimum speed of 128-kbps WAN throughput and 100-ms maximum roundtrip latency between each H-REAP and the wireless LAN controller.