Multimodal Security Mechanisms for Critical Time Systems using blockchain in Chriss project

Abstract - This paper presents an in-depth description of a multi-modal security solution based on a blockchain architecture developed within the CHRISS (Critical infrastructure High accuracy and Robustness increase Integrated Synchronization Solutions) project. Specifically, the focus in the paper is on the description of the proposed security architecture, functionalities and security measures based on modern blockchain solutions developed for the CHRISS project.

The CHRISS project proposes an innovative solution that comes to increase the robustness of synchronization signal distribution mechanisms in telecommunications networks. The proposed solution allows a superior monitoring of the operation of synchronization signal distribution equipment in telecommunications networks, equipment generically called TSU (Time Synchronization Unit). These equipment generically contain a GNSS (Global Navigation Satellite Systems) signal reception system from which the time reference is extracted through a complex procedure and a complex mechanism for transmitting these signals on SFP (Small Form-factor Pluggable) optical ports using the specific PTP (Precision Time Protocol) protocols. Robust and detailed monitoring of the operation of TSU equipment in the context of the existence of a hostile operating environment that implies the possibility of jamming or interference attacks, spoofing or dedicated cyber-attacks is vital. Affecting the operation of this equipment entails disruption to the operation of an entire telecommunications network. This is possible because these systems contribute directly to the network-wide distribution of the synchronization signal.

By leveraging the inherent characteristics of blockchain solutions, such as immutability, decentralization, and cryptographic security, the proposed security architecture increases the resilience and security of time distribution services, thereby mitigating the associated risks.

This paper describes the relationship between blockchain-based security architecture and the specific manner of monitoring and protecting TSU equipment.