# Federate Identity with Zephr This article focusses on setting up Zephr as your primary identity provider. It uses similar mechanisms than other identity systems (described in [How to federate your Authentication provider via OAuth and OpenID with Limio](https://docs.limio.com/product/authentication/sso-your-authentication)) with some enhanced settings to integrate more deeply Zephr with Limio. ### Set up a shared domain for Limio and Zephr For the Identity integration to work, Limio and Zephr needs to be on a shared domain. **In production:** Zephr customers typically integrate Limio on a shared domain between the Zephr site and the Limio Shop & Self-Service. For instance: * If you are using Zephr's paywall on a website hosted on news.com * And if you have a Limio Shop & Self-Service hosted on subscriptions.news.com Limio and Zephr Identity will operate smoothly on the same main domain (news.com). To configure Limio on your custom domain, visit [https://docs.limio.com/product/settings/how-to-add-your-custom-domain-to-limio](https://docs.limio.com/product/settings/how-to-add-your-custom-domain-to-limio "mention"). **Sandboxes:** Similarly to the production setup, we recommend you create shared domains, for example staging.news.com and subscriptions-staging.news.com. However, you may not be ready to configure custom domains for sandboxes. Limio can then set up a custom domain hosted in Limio to use in Zephr (e.g. zephr-news.prod.limio.com). This will allow to have a shared domain across your Zephr sandbox and your Limio sandbox. Please contact Limio Support with the title 'Request to create a Limio Domain to use in a Zephr sandbox'. Once created, you will then need to set up this domain in Zephr on Delivery > Sites > select a site > Domains. Learn more in [Zephr's documentation](https://knowledgecenter.zuora.com/Zephr/Delivery/Sites/Add_a_Site/Configure_Site_Domains). ### Set up Zephr Identity in Limio Limio can support v3 and v4 of Zephr Identity. Go to Limio Settings > Authentication Providers and click on 'Zephr Session' to set up identity federation with Limio. To do so, you will need to provide: 1. **Zephr Session Provider Name**: This is the domain (Limio or custom) for your Limio Shop & Self-Service instance. 2. **Registration/Login Redirect URL**: This URL is where users are sent to register or log in via Zephr. The `{{redirect_uri}}` placeholder dynamically inserts the return URL, so after logging in or registering, the user is redirected back to the original or intended page. 3. **Zephr Public API Endpoint**: This is the base URL for accessing Zephr's public API. The Public API provides common client-side actions tied to a session cookie. 4. **Zephr API Version**: Specifies the version of the Zephr API you're integrating with. API versions can have different features and capabilities. V4 is recommended. 5. **Salesforce Integration**: If you're integrating with Salesforce, this section defines how Zephr interacts with it. * **Account Profile Field**: This is the specific Salesforce field (e.g., 'sf-account-id') used in the integration, possibly for matching or syncing user accounts. 6. **Limio Session**: Configures the session settings in Limio. * **Session Length (Hours)**: The duration a user session remains active in Limio before requiring re-authentication. 7. **Field Mapping**: This maps fields between Zephr and Limio, ensuring data consistency and correct field population across both platforms. * **Zephr Field Name → Limio Field Name**: Each mapping line indicates how a field in Zephr (like 'first-name') corresponds to a field in Limio (like 'given\_name'). 8. **Zephr Private API Endpoint**: This endpoint is for Zephr's Admin API. The Admin API is designed for server-side integrations, and it provides RESTful access to all Zephr functionality. 9. **Access Key and Secret Key**: These are credentials for authenticating access to Zephr's private API. They ensure secure communication and access control. 10. **Site**: This setting likely specifies the particular site or digital property within your Zephr setup that these configurations apply to. Each of these settings plays a crucial role in ensuring that the identity federation between Limio and Zephr works seamlessly and securely, handling user data, sessions, and integrations efficiently.