# Network Identity Manager Concepts: Credentials Provider

Network Identity Manager relies on plug-ins to provide the majority of its functionality. A credentials provider is a plug-in that manages one or more types of credentials. The responsibilities of a credential provider are:

- to maintain the list of credentials and their properties for the supported type
- to monitor credential expiration
- to provide the logic necessary to obtain additional credentials once the identity provider has obtained the initial credential
- to provide the user interface panels necessary to permit the user to configure the credential provider

MIT Kerberos for Windows ships with two Network Identity Manager credential providers supporting Kerberos v5 and Kerberos v4. Credential providers for the Andrew File System and the Kerberized Certificate Authority are available separately.