What protocol does xytracking.net use?

Question

satellite navigation

What protocol does xytracking.net use to get data from GPS trackers?
All I managed to understand is that they have some kind of thing listening to www.xytracking.net:3381, you can telnet. The tracker itself sends the string *HQ,1312030015,ack# (The number is its ID) every n seconds to this address:port.
I tried to send this string via telnet and a Python TCP client, silence in response, although when you register a tracker on the site, it starts sending data there.

Answer 1

Answer: H02 tracker protocol
https://github.com/tananaev/traccar/commit/f278d3f...