+ - JP2_filename.jp2 is the name of a JP2 file available on the server.
+ - request type stateless for no caching, session (default) for caching
+ - return media type, JPT-stream tile based stream, or JPP-stream (default) precinct based stream
+ - auxiliary return protocol, tcp or udp (udp is not implemented yet), if not given, return data is filled in http chunk