DNaaS: Towards Scalable and Trusted Time-Sensitive Networks

Time-sensitive networks, as in IEEE TSN, serve safety-critical applications and are found in closed networks, such as avionics or in-vehicle networks. Validating the timing requirements in such networks requires obtaining proven latency bounds by using, for example, the network-calculus framework.

Although there exists a drive for scaling timesensitive networks to groups of networks with IETF DetNet, they do not scale beyond single-entity systems. Indeed, obtaining performance bounds requires the knowledge of all flows' and network's properties. This requirement is met when the system has a unique owner but is no longer satisfied when multiple stakeholders do not trust each other.

In this paper, we propose a framework that enables network operators to provide latency guarantees for traversing flows using zero-knowledge proofs. These proofs attest to the honest execution of networkcalculus algorithms (total flow analysis and its variant TFA++) and guarantee the fulfillment of timing requirements without revealing sensitive data. Moreover, we develop a smart contract to manage contractual relationships, orchestrate payments, and verify the validity of submitted proofs.

We also optimize the proof generation time and provide a proof of concept. Our scalability evaluations -including proof generation time and gas consumption -highlight the system's suitability for real-world deployment.