> For the complete documentation index, see [llms.txt](https://gl-docs.gitbook.io/zkpass/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gl-docs.gitbook.io/zkpass/zkpass-developers-guide/zkpass-modules/dvr/dvr-client-roles.md).

# DVR Client Roles

The DVR follows a robust trust model inspired by the W3C Decentralized Identifiers (DID) standards. Within the zkPass ecosystem, we define three client roles which participate in the zkPass ecosystem.

Depending on the application, the client of DVR can take one of these roles:

1. <mark style="color:orange;">**Data Issuer**</mark>\
   The entity responsible for issuing the original data that requires protection.
2. <mark style="color:orange;">**Data Holder (User)**</mark>\
   The individual whose confidential data is being protected.
3. <mark style="color:orange;">**Proof Verifier**</mark>\
   The service or application that sets the requirements or conditions on the user data. It verifies the zero-knowledge proof, which contains the result of the requirements.

This multi-faceted trust model allows the proper flow of data and communications among the DVR stakeholder clients and ensures that the user’s confidential information remains protected and secure.