How to differentiate a control path signal over data path signal?
The simple answer is, yes, you've done it correctly. But it can get more complicated than that.

In a "normal" computer, control and data information are both sent along a common path between a storage and an execution unit. In a PC, storage is ROM and/or RAM, and execution is the CPU. (And yes, within the CPU data and control paths become separate - don't worry about it.) 

This architecture is called a Von Neumann architecture, and is dominant in computers. However, it's perfectly possible to separate data and control from start to finish. This is called a Harvard architecture, and is sometimes seen, particularly in DSP systems. Probably the best-known current example is the Analog Devices SHARC line.