# DDHub Message Broker

## Overview

DDHub Message Broker is a component that primarily provides message routing, persisting, and delivery for a seamless data exchange between participants within an energy market or supply chain.

The message broker promotes sovereignty of participants by:

* The broker does not have authority or logic which assumes the power of the participants
* No one except the participant themselves can govern data exchange channels and verify messages
* Encryption/decryption, signature validation, authorization, etc must be done under the participants domain ([Client Gateway](https://docs.energyweb.org/legacy-documentation/ew-dos-technology-components-2023/decentralized-data-hub-ddhub/ddhub-client-gateway))

## DDHub Message Broker Component Diagram

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Below are the Message Broker components which need to be hosted to deploy a Decentralized Data Hub:

* Message Broker App
* NATS Jetstream and Jetstream Store to store small data messages (small messages up to 2 MB) and channel configurations
* Azure Blob (or other large file) Store for large data messages and delimited files converted into blobs, as well as file metadata
* RDBMS for message topic and schema management

<figure><img src="https://github.com/energywebfoundation/ewf-gitbook/blob/develop/.gitbook/assets/Screenshot%202023-05-02%20at%204.29.24%20PM.png" alt=""><figcaption></figcaption></figure>