Capacity of EM Side Channel Created by Instruction Executions in a Processor

This paper proposes a methodology to estimate leakage capacity of electromagnetic (EM) side channels created by execution of instruction sequences (e.g. a function, a procedure, or a program) in a processor. We propose to use Markov Source model to include the dependencies that exist in instruction sequence since each program code is written systematically to serve a specific task. The channel input sources are considered as the emitted EM signals while executing an instruction. We derive a mathematical relationship between the emanated instruction power (IP) and total emanated signal power while running a microbenchmark to obtain the channel input powers. The results demonstrate that leakages could be severe enough for a dedicated attacker to obtain some prominent information.