שאלה | Is the communication in the Sigfox protocol bi-directional and is it limited?

Is the communication in the Sigfox protocol bi-directional and is it limited?

		The communication in the Sigfox protocol bi-directional and the number of messages is UNLIMITED
		The communication in the Sigfox protocol bi-directional and number of DOWNLINK messages is limited to 4 per day, while the number of UPLINK messages is limited to 120 per day
		The communication in the Sigfox protocol is only FROM the device and the number of UPLINK messages is limited to 120 per day
		The communication in the Sigfox protocol is only FROM the device and the number of DOWNLINK messages is limited to 120 per da