A typical connection used to transmit/receive ARINC data might consist of a cable and a connector similar to the one shown below. Although ARINC transmit/receive channels aren't the only thing this interface can be used for. I've noticed that several different varieties of LRU also use some of the pin connections for I/O discretes.

So, are the I/O discretes considered to be part of the ARINC interface? Or do they just coincidentally share the same connector and have nothing to do with ARINC?