Issue link: https://read.uberflip.com/i/1428383
LoRaWAN 1.0.3 Specification ©2018 LoRa™ Alliance Page 32 of 72 The authors reserve the right to change specifications without notice. This is specifically useful to speed-up the acquisition of the class B beacon. The request has 888 no payload. 889 With the DeviceTimeAns command, the Network Server provides the network time to the end 890 device. The time provided is the network time captured at the end of the uplink transmission. 891 The command has a 5 bytes payload defined as follows: 892 893 Size (bytes) 4 1 DeviceTimeAns Payload 32-bit unsigned integer : Seconds since epoch* 8bits unsigned integer: fractional- second in ½^8 second steps Figure 10 : DeviceTimeAns payload format 894 The time provided by the network MUST have a worst case accuracy of +/-100mSec. 895 The DeviceTimeAns command MUST be sent as a class A downlink (i.e. over the RX1/RX2 896 receive windows of the Class A mode). (*) The GPS epoch (i.e Sunday January the 6 th 1980 897 at 00:00:00 UTC) is used as origin. The "seconds" field is the number of seconds elapsed 898 since the origin. This field is monotonically increasing by 1 every second. To convert this 899 field to UTC time, the leap seconds must be taken into account. 900 Example: Friday 12 th of February 2016 at 14:24:31 UTC corresponds to 901 1139322288 seconds since GPS epoch. As of June 2017, the GPS time 902 is 17seconds ahead of UTC time. 903 904 905