Home-realm discovery is the process of identifying and verifying a user's primary domain, also known as their home realm, during authentication. There are several synonyms that can be used to describe this process, including domain validation, realm detection, domain identification, and home realm detection. No matter the terminology, this process is crucial to ensure that users are authenticating with the correct credentials and accessing the appropriate resources. By accurately identifying a user's home realm, organizations can improve security measures and reduce the risk of unauthorized access. This can be especially important for large enterprises that have multiple domains and need to ensure that users are accessing the correct domain.