Server Properties - Security Page
Applies to: 
SQL Server
Use this page to view or modify your server security options.
Server Authentication
Windows Authentication mode
Uses Windows Authentication to validate attempted connections. If the sa password is blank when the security mode is being changed, the user is prompted to enter an sa password.
Important
Windows Authentication is much more secure than SQL Server Authentication. When possible, you should use Windows Authentication.
SQL Server and Windows Authentication mode
Uses mixed mode authentication to verify attempted connections, for backward compatibility with earlier versions of SQL Server. If the sa password is blank when the security mode is being changed, the user is prompted to enter an sa password.
Note
Changing the security configuration requires a restart of the service. When changing the Server Authentication to SQL Server and Windows Authentication mode the SA account is not automatically enabled. To use the SA account, execute ALTER LOGIN with the ENABLE option.
Login Auditing
None
Turns off login auditing.
Failed logins only
Audits unsuccessful logins only.
Successful logins only
Audits successful logins only.
Both failed and successful logins
Audits all login attempts.
Note
Changing the audit level requires restarting the service.
Server Proxy Account
Enable server proxy account
Enables an account for use by xp_cmdshell. Proxy accounts allow for the impersonation of logins, server roles, and database roles when an operating system command is being executed.
Caution
The login used by the server proxy account should have the least privileges required to perform the intended work. Excessive privileges for the proxy account could be used by a malicious user to compromise your system security.
Proxy account
Specify the proxy account used.
Password
Specify the password for the proxy account.
Options
Enable C2 audit tracing
Audits all attempts to access statements and objects and records them to a file in the \MSSQL\Data directory for default instances of SQL Server, or the \MSSQL$instancename\Data directory for named instances of SQL Server. For more information, see c2 audit mode Server Configuration Option.
Cross database ownership chaining
Select to allow the database to be the source or target of a cross-database ownership chain. For more information, see cross db ownership chaining Server Configuration Option.