Reliable Communication in Hybrid Authentication and Trust Models

TL;DR

This paper introduces DualRC, a new algorithm for reliable communication in hybrid authentication models that combines trusted nodes, dissemination paths, and digital signatures, enhancing robustness in distributed networks.

Contribution

It extends classical reliable communication protocols to hybrid models and proposes DualRC, leveraging trusted nodes and components for improved reliability.

Findings

DualRC effectively combines dissemination and digital signatures.

Algorithms verify reliable communication across network nodes.

Utilizes trusted nodes and components like Intel SGX enclaves.

Abstract

Reliable communication is a fundamental distributed communication abstraction that allows any two nodes of a network to communicate with each other. It is necessary for more powerful communication primitives, such as broadcast and consensus. Using different authentication models, two classical protocols implement reliable communication in unknown and sufficiently connected networks. In the first one, network links are authenticated, and processes rely on dissemination paths to authenticate messages. In the second one, processes generate digital signatures that are flooded in the network. This work considers the hybrid system model that combines authenticated links and authenticated processes. We additionally aim to leverage the possible presence of trusted nodes and trusted components in networks, which have been assumed in the scientific literature and in practice. We first extend the two classical reliable communication protocols to leverage trusted nodes. We then propose DualRC, a novel algorithm that enables reliable communication in the hybrid authentication model by manipulating both dissemination paths and digital signatures, and leverages the possible presence of trusted nodes (e.g., network gateways) and trusted components (e.g., Intel SGX enclaves). We provide correctness verification algorithms to assess whether our algorithms implement reliable communication for all nodes on a given network.