Q-ID: Lightweight Quantum Network Server Identification Through Fingerprinting

A quantum network comprises interconnected quantum servers capable of communication and collaboration for computational tasks. It is essential for quantum servers within this network to identify and authenticate one another. For instance, when a quantum server intends to execute a computational task on another machine, it becomes crucial for the quantum server to verify the authenticity of other quantum servers to maintain confidence in delegating computation. While several methods for fingerprinting these quantum computers have been proposed, many are resource-intensive and not currently practical. To address this, we introduce Q-ID, a lightweight fingerprinting method that accurately identifies quantum servers with negligible quantum computational demands. Q-ID operates by running a user's task circuit at two different levels of noise, using the resulting performance gap as a unique identifier for quantum servers. Additionally, we have developed an error evolution algorithm that allows users to locally estimate this performance gap. By comparing the estimated gap with the actual one, users can effectively identify or differentiate between quantum servers in a network. Our experiments on the IBM quantum platform showcase the efficacy and benefits of our approach.