a web service is iTop,
if i copy and paste this in the url
http://172.30.31.6/itop/web/webservices/rest.php?version=1.1&auth_user=admin&auth_pwd=admin&json_data={"operation":"core/create","class":"UserRequest","output_fields":"id","comment":"loquesea","fields":{"org_id":"1","title":"prueba_hospital",
"description":"prueba"}}
the server accept the request.
i need replicate that same in the POST of the arduino