For wireless unicast applications based on opportunistic network coding

each node caches some packets in a buffer called overhearing buffer for decoding.Traditional FIFO-based(First In First Out) overhearing management policy for "X" coding structure is discussed.With finite overhearing buffers

theoretical result shows that throughput decreases rapidly as the buffer size decreases.Therefore

we propose a Best Effort-based overhearing management policy

which improves the probability of cached packets to be used for decoding

and thus increases the system throughput.Furthermore

to buffer less useless packets

we propose an overhearing management policy based on historical information

which could effectively decrease the impact of interfering flows on system throughput.