Home > Storage > PowerScale (Isilon) > Product Documentation > Management and Migration > Dell PowerScale: Integrating OneFS with Kerberos Environment for Protocols > SMB authentication methods
As Figure 1 shows, the OneFS cluster will authenticate SMB users in the SMB session setup phase. Users can then create SMB sessions to access data stored on the cluster. OneFS supports two types of authentication methods for SMB: Kerberos and NTLM. Kerberos authentication is the first option in the SMB session setup. When Kerberos authentication is not available or failed, the authentication method will fall back to NTLM authentication.