transmitted in the past by a network node were presented in [@popovski06b] with the term bidirectional amplification of throughput (BAT) and in [@katabi07a] with the name ANC. A form of superposition coding in an X topology similar with the topology we have highlighted in Fig. \[fig:topology-mac-cc2\] was presented in [@katabi07a]. However, in that work the proposed system attempts to decode independently the overheard and relayed signals leading to higher number of packet failures while the baseline 802.11 MAC is used. Although in all these works the authors study more deeply relaying and ANC, they do not address problems like relay selection in this new context.

When we think about MAC issues in scenarios where ANC is employed, even fewer works exist. One of the most interesting works is the one by Boppana and Shea that proposed the overlapped CSMA protocol [@boppana:overlapped-csma]. The main task of that protocol is to estimate the level of secondary interfering transmissions that another primary transmission can sustain given its perfect knowledge of the signal that intends to cause the interference. This protocol requires significant signaling overhead in order to propagate RTS/CTS messages at least two hops and notify the secondary sender whether it is allowed 