Got ESP8266 working with RF Receiver. What is Protocol 12?

Integrations MQTT general
1

Finally got a working receiver RF up, could not get Sonoff RF Brdge up, even bought 2nd one. I have 3 types of old remotes, got one to work on ESP8266 & Receiver - that looks like this:
https://components101.com/433-mhz-rf-receiver-module.

Played around with uncommenting ZgatewayRF, ZgatewayRF2 and ZgatewayPilight to see which ones, or combinations will give me the most amnt of remote types that works. At then end I just left 1st 2 uncommented, which still only have one type of remote working.

The Topic home/OpenMQTTGateway/SYStoMQTT gives:
{"uptime":240,"freeMem":45000,"rssi":-82,"SSID":"TheStorm","modules":"RFRF2"}

And after RF remote button press, I get on Topic home/OpenMQTTGateway/433toMQTT
{"value":3086123042,"protocol":12,"length":64,"delay":407}

Question:

  1. What is Protocol 12 - where can I see what the protocols means?
2

Protocol 12 refer to the protocol number in rcswitch library, you can find more info here :
https://github.com/1technophile/OpenMQTTGateway/blob/development/lib/rc-switch/RCSwitch.cpp