Maintaining secure systems in the face of increasing information demands is a top priority for today’s enterprises. Businesses must satisfy the expanding information needs of their employees, customers, and partners while maintaining the highest levels of security for access to corporate systems and protecting the privacy of sensitive data.
SQL Server 2005, the next version of SQL Server 2005, will help organizations address these and other data management challenges by building on and adding to the security capabilities of SQL Server 2000.
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Realted link:
http://www.microsoft.com/sql/demos/2005/SQL%202005%20Security.swf

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Cheers,
~Danish Sami