Pontis: A decentralized framework for unifying remote attestation and enabling interoperability between heterogeneous TEEs

In modern decentralized information systems, establishing verifiable trust in remote computing environments has emerged as a critical challenge for secure cross-domain collaboration. Hardware-based Trusted Execution Environments (TEEs) such as Intel SGX and ARM TrustZone offer a promising foundation for addressing this challenge through cryptographically verifiable execution guarantees, but their incompatible Remote Attestation (RA) mechanisms create fundamental barriers to cross-platform trust establishment. Current solutions either focus on single-vendor ecosystems or introduce prohibitive architectural complexity, failing to address the critical need for lightweight, decentralized interoperability. This paper presents Pontis, a decentralized blockchain-based framework that solves unified RA and cross-platform communication challenges for heterogeneous TEEs through three key innovations: (1) a distributed off-chain Coordinator that normalizes vendor-specific attestation protocols, combined with blockchain-anchored decentralized identifiers that provide immutable distributed identities for TEE instances; (2) blockchain-based smart contracts implementing Registration, Attestation, and Management functions for immutable trust status propagation; and (3) secure cross-TEE communication channels built on the Noise protocol framework. Pontis reduces attestation complexity from O ( n 2 ) → O ( n ), achieving up to 99% reduction in required attestations for large-scale deployments. Comprehensive evaluations on heterogeneous TEE platforms, including Intel SGX and ARM TrustZone, demonstrate that Pontis maintains an attestation latency of 60 ms with over 10,000 TEE instances, while establishing a trusted channel between heterogeneous TEEs requires only 5 ms. These results demonstrate the robustness and feasibility of Pontis, establishing a robust foundation for secure, scalable, and flexible cross-platform collaboration in demanding heterogeneous computing environments.