Toward Interactive Debugging for ISP Networks.

The extreme complexity of Internet software leads to a rich variety of hard-to-isolate failure modes and anomalies. Research on debugging modern networked systems has thus far focused on “removing the human from the loop” by automatically detecting problems that violate predefined conditions. Here, we argue for a very different approach. Namely, we take the position that manual labor is a necessary evil of debugging problems in networked systems, but that this process would be vastly simpler with in-network support for debugging. We propose a network-layer substrate for interactive debugging that allows for tight controls on network execution, to provide reproducibility and performance isolation of the live network in highly distributed and dynamic environments.