BASIC. Authentication scheme where the user name and password are sent in clear-text to the server or proxy.
DIGEST. A challenge-response authentication scheme that uses a server-specified data string for the challenge.
NTLM. A challenge-response authentication scheme that uses the credentials of the user for authentication in a Windows network environment.
NEGOTIATE (also known as the Simple and Protected Negotiation protocol). A challenge-response authentication scheme that negotiates with the server or proxy to determine which scheme to use for authentication. Examples are the Kerberos protocol and NTLM.
PASSPORT. A centralized authentication service provided by Microsoft that offers a single logon for member sites.
Examples
To remove credentials from the job named myDownloadJob:
bitsadmin /removecredentials myDownloadJob SERVER BASIC