Secure and Dynamic Publish/Subscribe: LCMsec

TL;DR

LCMsec is a secure, brokerless Publish/Subscribe protocol extension that enhances IoT and automotive communications with low latency, high throughput, and robust security features using group key agreement and authenticated encryption.

Contribution

It introduces LCMsec, a novel decentralized protocol extension that integrates group discovery and secure messaging, reducing overhead compared to existing solutions.

Findings

Provides low-latency, high-throughput messaging for IoT and automotive applications.

Achieves enhanced security with group key agreement and authenticated encryption.

Reduces message authentication overhead compared to existing secure brokerless protocols.

Abstract

We propose LCMsec, a brokerless, decentralised Publish/Subscribe protocol. It aims to provide low-latency and high-throughput message-passing for IoT and automotive applications while providing much-needed security functionalities to combat emerging cyber-attacks in that domain. LCMsec is an extension for the Lightweight Communications and Marshalling (LCM) protocol. We extend this protocol by providing not only authenticated encryption of the messages in transit, but also a group discovery protocol inspired by the Raft consensus protocol. The Dutta-Barua group key agreement is used to agree upon a shared symmetric key among subscribers and publishers on a topic. By using a shared group key, we reduce the key agreement overhead and the number of message authentication codes (MACs) per message compared to existing proposals for secure brokerless Publish/Subscribe protocols, which establish a symmetric key between each publisher and subscriber and append multiple MACs to each message.