A common challenge when implementing SAML for identity integration between on-premise environment and an external identity provider service is that some users are not provisioned into the service. Provisioning is a process of creating, updating, or deleting the user accounts or profiles in a service or an application, based on the user identity or credentials. When implementing SAML for identity integration, the on-premise environment acts as the identity provider, which authenticates the user and issues the SAML assertion, and the external service acts as the service provider, which receives the SAML assertion and grants access to the user. However, if the user account or profile is not provisioned or synchronized in the external service, the user may not be able to access the service, even if they have a valid SAML assertion. Therefore, a common challenge when implementing SAML for identity integration is to ensure that the user provisioning is consistent and accurate between the on-premise environment and the external service. SAML tokens are provided by the on-premise identity provider, single users can be revoked from the service, and SAML tokens contain user information are not common challenges when implementing SAML for identity integration, as they are related to the functionality, granularity, or content of the SAML protocol, not the provisioning of the user accounts or profiles. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 5, Identity and Access Management, page 693. Official (ISC)2 CISSP CBK Reference, Fifth Edition, Chapter 5, Identity and Access Management, page 709.
