Where should an application connect to retrieve security tokens?

Applications retrieve security tokens from Azure Active Directory (Azure AD) for authentication and authorization purposes. Azure AD acts as an identity provider, issuing tokens (like OAuth 2.0 or OpenID Connect tokens) that applications can use to prove a user's identity and access protected resources. An Azure Storage account is used for storing data, not for issuing security tokens. A certificate store holds digital certificates, which are used for encryption and identity verification, but not for issuing runtime security tokens to applications. An Azure Key Vault securely stores cryptographic keys and secrets, but it doesn't issue security tokens for application authentication.