OLYMPIA: A Simulation Framework for Evaluating the Concrete Scalability of Secure Aggregation Protocols
Ivoline C. Ngong, Nicholas Gibson, Joseph P. Near
TL;DR
Olympia presents a simulation framework to enable end-to-end evaluation of secure aggregation protocols at scales unreachable by real hardware. It combines a Python-embedded DSL for protocol specification with an ABIDES-based simulator that models computation, network latency, bandwidth, and dropouts, providing realistic wall-clock timings. The authors implement multiple state-of-the-art protocols (including Bonawitz et al., Bell et al., Stevens et al., and ACORN) and perform a comprehensive empirical comparison across settings from hundreds to ten-thousand clients, revealing that computation often dominates total time and that server bandwidth can be a critical bottleneck. They validate Olympia’s accuracy against ground-truth deployments and show substantial speedups (e.g., simulating 10^4 clients on one machine) while offering new insights such as the limited impact of latency and the tangible gains from optimizations like packed secret sharing. The work provides open-source tooling and a standardized benchmark for future protocol development and deployment planning in large-scale secure aggregation for federated learning.
Abstract
Recent secure aggregation protocols enable privacy-preserving federated learning for high-dimensional models among thousands or even millions of participants. Due to the scale of these use cases, however, end-to-end empirical evaluation of these protocols is impossible. We present OLYMPIA, a framework for empirical evaluation of secure protocols via simulation. OLYMPIA. provides an embedded domain-specific language for defining protocols, and a simulation framework for evaluating their performance. We implement several recent secure aggregation protocols using OLYMPIA, and perform the first empirical comparison of their end-to-end running times. We release OLYMPIA as open source.
