The documentation portal is undergoing maintenance. During this period, you can't create any new user credentials. If you do, you'll need to recreate the user credential after the maintenance period ends.
Effective in version 10.5.1, you can configure an Informatica domain that uses Kerberos authentication to use constrained delegation.
Configure constrained delegation when you want to restrict access to services using delegated authentication. You can use this method to restrict the additional services to which a Kerberos-authenticated user or service can request access.