SQL Server 2005 supports native XML web services for both SOAP 1.1 and SOAP 1.2 clients. The SQL Server Database Engine can be configured as an HTTP listener, allowing heterogeneous clients to access its data. You can send SOAP message requests to SQL Server over HTTP to execute T-SQL batch statements (with or without parameters), stored procedures, extended stored procedures, and scalar-valued user-defined functions (UDFs).
In SQL Server 2000, web service support is provided by SQLXML 3.0 and Internet Information Services (IIS), as well as the Microsoft Data Access Components (MDAC) stack installed on the client to access SQL Server. The inclusion of native web services in SQL Server 2005 allows a much wider group of clients to access the database, consistent with the platform and operating system interoperability goals for web services.
A client needs only HTTP and XML to access web services exposed by SQL Server 2005. This broadens access to SQL Server data across the extended enterprise from heterogeneous environments, including Unix and Linux systems and mobile devices. SQL Server 2005 includes built-in security measures to control client access.