— Asymmetric links are common in wireless networks for a variety of physical, logical, operational, and legal considerations. An asymmetric link supports uni-directional communication between a pair of mobile stations and requires a set of relay stations for the transmission of packets in the other direction. We introduce a MAC layer protocol for wireless networks with asymmetric links (AMAC). The MAC layer protocol requires fewer nodes to maintain silence during a transmission exchange than the protocols proposed in [1], [2]. We present a set of concepts and metrics characterizing the ability of a medium access control protocol to silence nodes which could cause collisions.