Dynamic Security Parameters for Multichannel Secret Sharing Protocols

Multichannel secret sharing protocols generalize performance-oriented multipath protocols like Multipath TCP [1], exploiting path diversity to bolster confidentiality, data integrity, or availability in addition to throughput. The appropriate balance between these security and performance properties is not fixed; rather, it shifts over time depending on a variety of factors, including user preference and risk assessment. In this paper, we present a multichannel secret sharing protocol which provides a general mechanism for altering security parameters in response to current defensive priorities. This work includes a novel share-buffering algorithm to address the disconnect between the assumptions of TCP congestion control and the behavior of multichannel protocols with several threads. We run a series of simulated attacks against our new protocol, demonstrating the effect of changing each parameter in the presence of attackers of various strengths. Our results also show that, as a result of the new share buffer, a multithreaded implementation now achieves over 90% of the theoretical maximum. This work paves the way to adaptive multichannel security for data in transit, layering a flexible and practical "second factor" atop conventional encryption techniques.