Its AEB sir first introduced by GY in their Alcos doing braking duties at Braganza Ghats after that when EMDs invaded this route UBL shed fitted AEB too in their WDG4s which do braking duties at Braganza and Shiradi Ghats of SWR territory.
Basics of this braking system are each loco has a specific key which is given to the LP while descending the Ghats at CLR where the brakers are attached and by this if the train exceeds a specific speed in this case its 30kph the brakes are immediately applied and the train comes to a halt. Once the locos reach QLM the end of the Ghat section the brakers are detached and later they act as bankers to...
more... an uphill train once it reaches CLR the LPs return back the keys to the station master at CLR and next time same procedure repeats.
This is just the basic procedure it has lots of technical aspects to it which I'm not well aware of.