Gopisathya

1.  IDP (Identity provider) Azure AD 2. SP (service provider) Any of your applications like Joomla, Moodle, Drupal 3. Authentication can be done via OAuth, SAML etc.. between IDP and SP. 4. Microsoft Office 365 uses Azure AD to authenticate users. 5.  OpenID Connect is an identity layer built on top of OAuth 2.0, providing authentication capabilities.

 In case, a config import error is coming because the new module is not installed then we can do the following function somemodule_update_10001() {   if (!\Drupal::service('module_handler')->moduleExists('new_module')) {     \Drupal::service('module_installer')->install(['new_module']);   } }