On Function Computation over a Cascade Network (Invited Paper)

International audience<p>A transmitter has access to X, a relay has access to Y , and a receiver has access to Z and wants to compute a given function f(X; Y;Z). How many bits must be transmitted from the transmitter to the relay and from the relay to the receiverso that the latter can reliably recover f(X; Y;Z)?The main result is an inner bound to the rate region of thisproblem which is tight when (X,Y,Z) forms a Markov chain.</p