Hello @TUHIN SINHA , you will find my answers to your questions below them.
- Mobile Integration : Considering Azure b2c needs to redirect to external IDP and considering different flow, What are the prerequisite for mobile app in IOS or android to be integrated with Azure B2C ?. Current system is using API for registration and login. Can we leverage Microsoft graph Ui for login and registration for local user?
Take a look to Enable authentication in your own Android app by using Azure AD B2C and Enable authentication in your own Android app by using Azure AD B2C - Migrate Client secret : Can we migrate existing OIDC clientid / client secret from Secure Auth to AzureB2C ? Whether OIDC setup need to be re-establish with the vendor?
Client ids are auto-generated in Azure AD B2C so those cannot be migrated. You may implement a mapping table between your old and new ids. Client secrets can however it's not recommended. - Password hash from Azure b2c : If we need to migrate from Azure B2C to any other CIAM , can we migrate Password hash / salt to the new CIAM if required?
No, this is not possible. However you can read user credentials trough User migration. - Environment : Do we need to setup new tenant for each environment?
Yes, this is a common practice. - Data Refresh : Can we refresh data from production environment and perform masking of the specific field?
What do you mean with this?
Also, take a look to Migrate users to Azure AD B2C, Manage Azure AD B2C with Microsoft Graph and SecureAuth IdP API Documents.
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