That sounds like an interesting problem. Right now, though, it sounds rather vague. There are any number of ways of accomplishing this in LabVIEW, so it would probably help to know what types of signals you'll be sending, whether the process should run continuously, etc.
For now I came up with an example that sends values from A to B to C. You can specify the delay time for the signals to "travel" from A to B and from B to C respectively. In reality, what I did was to bundle each signal into a cluster with a start time. Then I pass each new signal in a buffered queue to another loop which checks how old each new incoming signal is. If it is old enough (the propagation time has elapsed), then the signal is displayed at position B and is passed onto C, which repeats this process.
I used LabVIEW queues to accomplish this. To transmit numerical values, you might also consider using Waveform data types, which similar to my example bundle together timing information (t0) and an array of Y-values for the signal. Check it out, I hope this helps!
Jarrod S.
National Instruments