Home > Data Protection > PowerProtect DD Series Appliances > Dell PowerProtect DD Series Appliances: Security > DDOS system interfaces and access control
Hosts and backup applications interface with PowerProtect DD appliances through one or more of the standard native server interface protocols: CIFS, NFS, NDMP, VTL, and DD Boost.
Access control and user authentication to the system is controlled by either local users, NIS environments, or LDAP, or within a Microsoft Active Directory Domain environment. The following figure shows other security attributes of the system.