  This paper focuses on the capacity of point-to-point relay communications
wherein the transmitter is assisted by an intermediate relay. We detail the
mathematical model of cutset and amplify and forward (AF) relaying strategy. We
present the upper bound capacity of each relaying strategy from information
theory viewpoint and also in networks with Gaussian channels. We exemplify
various outer region capacities of the addressed strategies with two different
case studies. The results exhibit that in low signal-to-noise ratio (SNR)
environments the cutset performance is better than amplify and forward
strategy.
