> For the complete documentation index, see [llms.txt](https://qualitax.gitbook.io/interop/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://qualitax.gitbook.io/interop/requirements/foundational-layer/messaging-sub-layer.md). # Messaging sub-layer **Focus**: Secure, verifiable, and standardized communication between chains. **Objective**: Enable trusted data exchange between chains. Facilitate the trusted exchange of information between blockchains, ensuring that participants on a receiving blockchain can verify the authenticity and integrity of the information coming from another blockchain. **Description**: Provides standardized message formats, protocols, and infrastructure for reliable messaging and data exchange between interconnected blockchains. The Messaging Layer provides the protocols, standards, and tools required for this communication. It ensures that messages are not just transmitted, but also can be trusted. This might involve cryptographic proofs, attestations, or other mechanisms that certify the authenticity of a message. Especially in regulated environments, ensuring the confidentiality, integrity, and authenticity of crosschain messages is paramount to comply with data protection, security, and other regulatory mandates. **Layer owner**: Crosschain protocol developers, smart contract developers. Some key aspects: * Common addressing schemes and message routing * Message serialization formats like JSON * Delivery guarantees like at-most-once, at-least-once * Retry and recovery mechanisms * Trusted message transport protocols * Encryption and data privacy * Quality of service and service level objectives * Interfacing with external message queues * Message orchestration, workflow and streaming --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://qualitax.gitbook.io/interop/requirements/foundational-layer/messaging-sub-layer.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.