Identifying malicious communications by generating data representative of network traffic based on adaptive sampling includes, at a computing device having connectivity to a network, obtaining a set of data flows representing network traffic between one or more nodes in the network and one or more domains outside of the network, wherein each data flow in the set of data flows includes a plurality of data packets. One or more features are extracted from the set of data flows based on statistical measurements of the set of data flows. The set of data flows are adaptively sampled based on at least the one or more features. Then, data representative of the network traffic is generated based on the adaptively sampling to identify malicious communication channels in the network traffic.