> For the complete documentation index, see [llms.txt](https://docs.energyweb.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.energyweb.org/legacy-documentation/ew-dos-technology-components-2023/decentralized-data-hub-ddhub.md).

# Decentralized Data Hub (DDHub)

The Decentralized Data Hub (DDHub) is one of the primary technologies underpinning [EW Data Exchange](https://github.com/energywebfoundation/ewf-gitbook/blob/develop/solutions/data-exchange/README.md) solutions. The DDHub Environment is composed of multiple DDHub Messaging Client Nodes interacting with each other through the DDHub Message Broker.

* Each node (or group of nodes) in the Message Broker cluster is identified with a unique [DID](https://github.com/energywebfoundation/ewf-gitbook/blob/develop/foundational-concepts/self-sovereign-identity-ssi.md) and must be issued with a DDHub Messaging Client role
* Each node contains an [IAM Client ](broken://pages/1CETmO29GTp6VaGtxgsk)that ensures legitimacy of users interacting within the messaging cluster by checking their identities, and issued role or set of roles\\
* The IAM Client and DIDs provide a layer of protection against unauthorized access to DDHub functionalities
* Data exchanged within the cluster is secured in transit with mTLS

<figure><img src="/files/2LokF6OJTtP2Hg8UjUKW" alt=""><figcaption></figcaption></figure>


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