Check out the downlink README to better understand the overall downlink mechanism over the Sigfox network
This sample use the hapi framework. Check their website for install instructions.
$ node hapi.js
$ curl -X POST http://localhost:4004/sigfox-downlink-empty -H "content-type: application/json" -d '{"device":"FAF7E"}'
< HTTP/1.1 204 No Content
$ curl -X POST http://localhost:4004/sigfox-downlink-data -H "content-type: application/json" -d '{"device":"FAF7E", "data":"70117f61a5ceec67"}'
< HTTP/1.1 200 OK
< content-type: application/json; charset=utf-8
{"deviceId":"FAF7E","downlinkData":"70117f61a5ceec67"}