Exploiting Process Variations to Secure Photonic NoC Architectures from Snooping Attacks

The compact size and high wavelength-selectivity of microring resonators (MRs) enable photonic networks-on-chip (PNoCs) to utilize dense-wavelength-division-multiplexing (DWDM) in their photonic waveguides, and as a result, attain high bandwidth on-chip data transfers. Unfortunately, a hardware Trojan (HT) in a PNoC can manipulate the electrical driving circuit of its MRs to cause the MRs to snoop data from the neighboring wavelength channels in a shared photonic waveguide, which introduces a serious security threat. This article presents a framework that utilizes process variation-based authentication signatures along with architecture-level enhancements to protect against data-snooping HT during unicast as well as multicast transfers in PNoCs. The evaluation results indicate that our framework can improve hardware security across various PNoC architectures with minimal overheads of up to 14.2% in average latency and of up to 14.6% in energy-delay-product (EDP).