Device Connection State

hhamedk, you can check time of unit's last message and if it is older than 10 minutes mark it as not connected.

hhamedk, you can use this method - if any "tcp" or "udp" command is available - then unit has active GPRS connection to server.

Denisse, for now You can do it like this:
1. set Available commands data flag (https://sdk.wialon.com/wiki/en/sidebar/ … e_commands)
2. then You can get unit's currently available commands:
unit.getCommands()
3. in resulting array check if any command contains "tcp" or "udp" value in "t" parameter (for example "tcp,gsm").
If contains - unit has active GPRS connection.

Denisse, You can do it in cycle for all units.
Like this:

var onlineUnits = [];
var units = wialon.core.Session.getInstance().getItems("avl_unit");
for (var i = 0; i < units.length; i++) {
var unit = units[i];
if (!unit)
continue;
var cmds = unit.getCommands();
if (!cmds)
continue;
for (var j = 0; j < cmds.length; j++) {
var cmd = cmds[j];
if (cmd.t.indexOf("tcp") >=0 || cmd.t.indexOf("udp") >=0)
onlineUnits.push(unit.getId());
}
}

This way is not very convenient but soon there will be available additional unit's paramter which will indicate is unit online or offline.