How do you communicate with Photon, is it over HTTP? (I know nothing of this "JAX-RS" you speak of). I was thinking of building something like this for my photo warping app Trollaroid -- currently all the processing is done on client devices, but it'd be much more sensible to do it in the cloud. How might hooking up my API endpoint to an array of Java image processors over HTTP compare to say, using ZeroMQ as the glue?