digital sync so there are no digital drop outs "pops and clicks" is more a word clock sync and usually part of the house sync, digital equipment hand shaking such as digital converters say i wanted to convert madi to aes/ebu through an external box and then maybe the aes to analog..thats mostly digital processing to keep clocking of ones and zeros in order ...
Timing and positional reference in terms of location play rewind mmc smpte LTC and many more were used.. but new time stamp protocols.. for example most new codes are passed through ethernet or usb...a program map is used... example from behringer xcontrol (yes cheap crap but works well)
"Supports HUI* and Mackie Control* protocols for seamless integration with every compatible music production software"
its back to my point that these companies that are so called leaders in the field are writing hui codes and if your a manufacturer and want to use the code, you may need to License it...from digidesigm/AVID.. Klark technik etc..question is ..are there developer hacks or a way to read the real time info..??