This repository accompanies the theoretical and academic research efforts around blockchain interoperability within the Hyperledger Cacti ecosystem.
The purpose of this project is to:
- Aggregate and systematize the growing body of scientific work on blockchain interoperability, especially as it relates to Hyperledger Cacti and related frameworks.
- Provide a curated, structured overview of theoretical, methodological, and empirical research in the domain.
- Serve as a foundation for new research, by offering a unified reference point for academic publications, taxonomies, and conceptual mappings.
This repository is jointly maintained by INESC-ID and Técnico Lisboa, with contributions from the Hyperledger Cacti research and development community.
Blockchain interoperability remains one of the most significant challenges in distributed ledger research and adoption. While Hyperledger Cacti and other frameworks provide practical implementations, there exists a fragmented theoretical landscape — spanning multiple dimensions:
- Security and trust models
- Architectural patterns for interoperability mechanisms (IMs)
- Privacy and confidentiality frameworks
- Theoretical foundations for cross-chain communication
This repository aims to bridge theory and practice, by documenting and categorizing the state of the art and state of the practice in interoperability research.
interoperability-theory/
│
├── README.md ← This document
├── papers/ ← Directory for collected academic papers
│ ├── <paper_name>.pdf
│ ├── ...
│
├── abstracts/ ← Extracted abstracts from the papers
│ ├── <paper_name>.md
│ ├── ...
│
├── tables/ ← Summaries and mappings in table format
│ ├── interoperability-index.csv
│ ├── methodology-classification.csv
│ ├── topics-taxonomy.csv
│
├── figures/ ← Figures, diagrams, and visual digests
│ ├── <conceptual_diagram>.png
│ ├── ...
│
├── digest/ ← Theoretical digests summarizing contributions
│ ├── <digest_topic>.md
│ ├── ...
│
└── latex-paper/ ← LaTeX project for the accompanying paper
├── main.tex
├── bibliography.bib
├── sections/
├── figures/
└── ...
Below is the planned structure for the comprehensive paper index.
| Year | Title | Authors | Venue | Category | Topics | Link |
|---|---|---|---|---|---|---|
| 2025 | Enabling Semantic Blockchain Interoperability Across Heterogeneous Infrastructures | C. Amaro, R. Belchior, A. Vasconcelos, M. Correia | The 1st IEEE International Conference on Distributed Ledger Technology (2026) | Ontologies / Semantic Interoperability | Semantic interoperability, Heterogeneous infrastructures, Blockchain integration | -- |
| 2025 | Automatic Cross-chain Protocol Pausing with Real-time Conformance Checking | B. Mateus, A. Vasconcelos, M. Correia, A. Augusto, R. Belchior | 7th Conference on Blockchain Research & Applications for Innovative Networks (2025) | Theoretical / Runtime Enforcement | Runtime pausing, Conformance checking, Safety | -- |
| 2025 | Visualization of Cross-Chain Transactions for Secure Blockchain Interoperability (Position Paper) | J. Santos, A. Augusto, A. Vasconcelos, M. Correia | 20th European Dependable Computing Conference Companion Proceedings (2025) | Position | Cross-chain transactions, Security, Visualization | -- |
| 2025 | Handling Assets in the Secure Asset Transfer Protocol—One Schema to Handle Them All (Position Paper) | R. Carapau, A. Augusto, A. Vasconcelos, M. Correia | 20th European Dependable Computing Conference Companion Proceedings (2025) | Position | Asset handling, SATP, Schema design | -- |
| 2025 | Blockchain Interoperability: Theory and Practice | A. Augusto, R. Belchior, J. Pfannschmidt, A. Vasconcelos, M. Correia | IEEE ICBC (2025) | Tutorial | Interoperability theory, Practical approaches | 🔗 Link |
| 2025 | Looking for Anomalies in Cross-Chain Bridges | A. Augusto, R. Belchior, J. Pfannschmidt, A. Vasconcelos, M. Correia | IEEE/IFIP Dependable Systems (2025) | Practical / Monitoring | Bridge anomalies, detection, evaluation | 🔗 Link |
| 2025 | XChainDataGen: A Cross-Chain Dataset Generation Framework | André Augusto, André Vasconcelos, Miguel Correia, Luyao Zhang | Preprint (March 2025) | Tooling / Dataset | Dataset generation, Evaluation frameworks, Cross-chain traces | 🔗 Link |
| 2025 | XChainWatcher: Identifying Anomalies in Cross-Chain Bridges | André Augusto, Rafael Belchior, Jonas Pfannschmidt, Miguel Correia, André Vasconcelos | ACM/IFIP Int. Middleware Conference (Middleware) (2025) | System / Monitoring | Anomaly detection, Bridges monitoring, Security | 🔗 Link |
| 2025 | Gateways for Institutional-Grade Commerce and Interoperability of Digital Assets | R. Belchior, T. Hardjono, A. Chiriac, V. Ramakrishna | arXiv preprint (arXiv:2501.17732) (2025) | Preprint / Design | Gateways, Institutional-grade interoperability | 🔗 Link |
| 2024 | An Enterprise Architecture Approach to Semantic Blockchain Interoperability | S. Mayor, R. Belchior, M. Correia, A. Vasconcelos | ICEIS (2024) | Theoretical / Architecture | Semantic interoperability, Enterprise integration | 🔗 Link |
| 2024 | Towards a Standard Framework for Blockchain Interoperability: A Position Paper | R. Belchior, S. Scuri, N. Nunes, T. Hardjono, A. Vasconcelos | IEEE ICBC (2024) (position paper) | Position / Standards | Standardization, Frameworks, Interoperability layers | 🔗 Link |
| 2024 | A Brief History of Blockchain Interoperability | R. Belchior, J. Süßenguth, Q. Feng, T. Hardjono, A. Vasconcelos, M. Correia | Communications of the ACM (CACM) (2024) | Survey / Historical | Historical timeline, evolution of interoperability approaches | 🔗 Link |
| 2024 | BUNGEE: Dependable Blockchain Views for Interoperability | R. Belchior, L. Torres, J. Pfannschmid, A. Vasconcelos, M. Correia | ACM DLT — Distributed Ledger Technologies: Research and Practice (2024) | System / Mechanism | Dependable views, State sharing, IM designs | 🔗 Link |
| 2024 | Multi-Party Cross-Chain Asset Transfers | A. Augusto, R. Belchior, A. Vasconcelos, T. Hardjono | IEEE ICBC (2024) | Theoretical / Protocol | Multi-party transfers, Atomicity, Protocol design | 🔗 Link |
| 2024 | Benchmarking Blockchain Bridge Aggregators | S. Subramanian, A. Augusto, R. Belchior, A. Vasconcelos, M. Correia | IEEE Int. Conf. on Blockchain (Blockchain) (2024) | Benchmarking / Practical | Performance benchmarking, Bridge aggregators | 🔗 Link |
| 2024 | SoK: Security and Privacy of Blockchain Interoperability | A. Augusto, R. Belchior, M. Correia, A. Vasconcelos, L. Zhang, T. Hardjono | IEEE Symposium on Security and Privacy (S&P) (2024) | SoK / Survey | Security models, Privacy threats, IM threat taxonomy | 🔗 Link |
| 2023 | Harmonia: Securing Cross-Chain Applications Using Zero-Knowledge Proofs | R. Belchior, D. Dimov, Z. Karadjov, J. Pfannschmidt, A. Vasconcelos, … | TechRxiv / preprint (2023) | Theoretical / Cryptographic | ZK proofs, Privacy, Cross-chain security | 🔗 Link |
| 2023 | CBDC bridging between Hyperledger Fabric and permissioned EVM-based blockchains | A. Augusto, R. Belchior, I. Kocsis, L. Gönczy, A. Vasconcelos, M. Correia | IEEE ICBC (2023) | Practical / Use-case | CBDC, Fabric ↔ EVM bridges, Interoperability engineering | 🔗 Link |
| 2023 | Hephaestus: Modelling, Analysis, and Performance Evaluation of Cross-Chain Transactions | R. Belchior, P. Somogyvari, J. Pfannschmid, A. Vasconcelos, M. Correia | IEEE Transactions on Reliability (2023) | Theoretical / Evaluation | Cross-chain transaction modelling, performance analysis | 🔗 Link |
| 2023 | Do You Need a Distributed Ledger Technology Interoperability Solution? | R. Belchior, L. Riley, T. Hardjono, A. Vasconcelos, M. Correia | ACM DLT — Distributed Ledger Technologies: Research and Practice (2023) | Position / Survey | Interoperability decision factors, use-cases | 🔗 Link |
| 2022 | Trustable Blockchain Interoperability: Securing Asset Transfers on Permissioned Blockchains | C. Pedreira, R. Belchior, M. Matos, A. Vasconcelos | BlockTEE (2022) | Practical / Security | Permissioned chains, Secure transfers | 🔗 Link |
| 2022 | A Survey on Business Process View Integration: Past, Present and Future Applications to Blockchain | R. Belchior, S. Guerreiro, A. Vasconcelos, M. Correia | Business Process Management Journal (2022) | Survey / Application | Business processes, Integration, Blockchain use-cases | papers/survey-bpm-blockchain-2022.pdf |
| 2022 | Secure Asset Transfer Protocol (SATP) | M. Hargreaves, T. Hardjono, R. Belchior | IETF SATP Working Group / Protocol (2022) | Protocol / Standard | Asset transfer, Gateway protocol | 🔗 Link |
| 2022 | HERMES: Fault-Tolerant Middleware for Blockchain Interoperability | R. Belchior, A. Vasconcelos, M. Correia, T. Hardjono | Future Generation Computer Systems 129 (April 2022) | System / Middleware | Fault tolerance, Middleware, IMs | papers/hermes-fgcs-2022.pdf |
| 2021 | SATP Gateway Crash Recovery Mechanism (draft) | R. Belchior, M. Correia, A. Augusto, T. Hardjono | IETF draft (gateway recovery) (2021) | Protocol / Standard draft | SATP, Gateway resilience, Recovery | 🔗 Link |
| 2021 | Enabling Cross-Jurisdiction Digital Asset Transfer | R. Belchior, A. Vasconcelos, M. Correia, T. Hardjono | IEEE Int. Conf. on Services Computing (2021) | Theoretical / Position | Cross-jurisdiction asset transfer, legal/technical bridges | papers/cross-jurisdiction-2021.pdf |
| 2021 | A Pub-Sub Architecture to Promote Blockchain Interoperability | S. Ghaemi, S. Rouhani, R. Belchior, R. Cruz, H. Khazaei, P. Musilek | arXiv preprint arXiv:2101.12331 (2021) | Design / Preprint | Pub-Sub, Messaging, Interoperability patterns | 🔗 Link |
| 2021 | Distributed attribute-based access control system using permissioned blockchain | S. Rouhani, R. Belchior, R.S. Cruz, R. Deters | World Wide Web Journal 24(5), 1617–1644 (2021) | Practical / System | Attribute-Based Access Control, Permissioned ledgers | papers/distributed-abac-2021.pdf |
| 2021 | A Survey on Blockchain Interoperability: Past, Present, and Future Trends | R. Belchior, A. Vasconcelos, S. Guerreiro, M. Correia | ACM Computing Surveys (CSUR) 54(8), 1–41 (2021) | Survey / SoK | Interoperability taxonomy, historical trends | papers/survey-interoperability-csur-2021.pdf |
| 2020 | Towards Secure, Decentralized, and Automatic Audits With Blockchain | R. Belchior, M. Correia, A. Vasconcelos | European Conference on Information Systems (ECIS) (2020) | Practical / Position | Auditing, Decentralized assurance | papers/audits-blockchain-2020.pdf |
| 2020 | SSIBAC: Self-Sovereign Identity Based Access Control | R. Belchior, B. Putz, G. Pernul, M. Correia, A. Vasconcelos, S. Guerreiro | 3rd Int. Workshop on Blockchain Systems and Applications (2020) | Practical / Access Control | Identity, Access Control, SSI | papers/ssibac-2020.pdf |
| 2019 | Justicechain: Using blockchain to protect justice logs | R. Belchior, M. Correia, A. Vasconcelos | OTM Confederated Conferences (2019) | System / Application | Auditability, Integrity, Judicial logs | papers/justicechain-2019.pdf |
| 2019 | Hyperledger Cactus — Whitepaper | H. Montgomery, H. Borne-Pons, J. Hamilton, M. Bowman, P. Somogyvári, … | Hyperledger Cactus (project whitepaper) | Tooling / Project Whitepaper | Architecture, Interoperability platform | 🔗 Link |
Categories:
- 🧩 SoK / Survey — Systematization of Knowledge papers summarizing the field.
- 🧠 Theoretical Proposal — Conceptual or mathematical models for interoperability.
- ⚙️ Practical Proposal — Implementations, frameworks, or empirical evaluations.
Topics:
- 🔐 Security
- 🕵️ Privacy
- 🏗️ Architecture / Design
- 🔗 Interoperability Mechanisms (IMs)
- 🧮 Formal Models
- 🌐 Cross-Chain Communication
The repository aggregates content based on multiple dimensions:
| Dimension | Description | Example Values |
|---|---|---|
| Methodology | Nature of the paper’s contribution | SoK, Theoretical Model, Implementation |
| Topic | Thematic focus | Security, Privacy, Architecture |
| Scope | Layer or abstraction level | Protocol-level, Application-level |
| Frameworks Studied | Frameworks analyzed in the paper | Hyperledger Cacti, Polkadot, Cosmos, Chainlink CCIP |
| Interoperability Model | Type of IM studied | Relay, Notary, Hash-locking, Bridging, Hybrid |
A script (to be added in future versions) will automate classification and table generation from metadata files.
Each digest summarizes key concepts, models, and contributions from a subset of the literature.
Example topics include:
- Taxonomy of Blockchain Interoperability Mechanisms (IMs)
- Security Assumptions in Cross-Chain Systems
- Privacy Models and Zero-Knowledge Interoperability
- Architectural Patterns for Multi-chain Networks
- Standardization Efforts (W3C, ISO, Hyperledger)
These digests are located in the digest/ directory and are linked to corresponding figures in figures/.
We welcome contributions from researchers and practitioners interested in blockchain interoperability theory.
- Fork the repository
- Add or update:
- Papers and abstracts
- Tables or taxonomies
- Conceptual digests or figures
- Submit a Pull Request (PR) with a clear description of your addition
- Ensure all papers are open-access or properly cited
- Follow the existing table formats for consistency
- Keep figures lightweight and clear
Maintainers
- Andre Augusto (INESC-ID, Técnico Lisboa)
- Rafael Belchior (INESC-ID, Técnico Lisboa, Blockdaemon)
- Carlos Amaro (INESC-ID, Técnico Lisboa)