XIM: The XDC Interledger Messaging Protocol

XIM (The XDC Interledger Messaging Protocol) is a chain-agnostic protocol designed to transport canonical authenticated messages across heterogeneous financial rails, including public blockchains, permissioned ledgers, and conventional payment systems. Submitted to arXiv on September 30, 2026, by researchers from XDC Network Research and Engineering, it enables interoperability without requiring a shared execution environment or global state replication.

The protocol achieves this through several key architectural features: Separation of Concerns: XIM decouples message semantics from transport, verification, execution, and compliance, allowing each communication lane to select an explicit verification policy (e.g., light clients, zero-knowledge proofs, or threshold attestations). Universal Asset Identifier (UAID): It standardizes asset identity across chains, separating economic asset identity from chain-specific token contract addresses. Cryptographic Commitments: State is represented by deterministic message identifiers and Sparse Merkle Tree commitment roots, ensuring auditability and replay protection without replicating foreign-chain data. Gateway Integration: It supports ISO 20022-compatible workflows, allowing authenticated financial instructions from legacy systems to be mapped into XIM intents via trusted gateways.

XIM does not mandate the XDC Network for all routing; instead, XDC serves as an optional coordination and settlement domain, preserving protocol neutrality while allowing applications to leverage XDC’s infrastructure where it best fits specific settlement requirements.

Summary

The paper presents XIM, an interledger messaging protocol for the XDC ecosystem, targeting a practical gap in financial and blockchain interoperability: the need to move both authenticated messages and settleable assets across systems with different trust models. It frames the problem in terms of three common classes of interoperability systems—those focused on application-level abstraction, cross-chain message transport, or settlement mechanics—and argues that real-world institutional environments often require more than any single one of these. Distributed public ledgers, permissioned or privacy-preserving institutional networks, and conventional payment rails all need a shared way to communicate securely while preserving enough verification to support value transfer.

XIM’s central contribution is to treat interledger communication as a messaging and settlement coordination problem, rather than merely a data-forwarding problem. The protocol is positioned to provide authenticated, verifiable message exchange across heterogeneous trust domains, with the goal of enabling cross-ledger operations and asset settlement without requiring every participant to share the same consensus model, data visibility assumptions, or application semantics. In doing so, it aims to give institutional networks a more composable interoperability layer: one that can bridge privacy-sensitive enterprise networks, public chains, and legacy payment systems while maintaining clear boundaries of trust, authentication, and settlement responsibility.

This matters because institutional finance is increasingly composed of heterogeneous systems that must interoperate without sacrificing privacy, auditability, or regulatory constraints. A protocol like XIM could reduce the fragmentation between blockchain-based ledgers, permissioned enterprise networks, and traditional payment infrastructure by providing a common messaging substrate for cross-domain transactions. If successful, such a layer would make cross-ledger payments, asset exchange, and institutional settlement more practical, especially in settings where full transparency is not feasible but authenticated, verifiable interoperability is still required.