With the popularity of RSS feeds, many products support the XML data format. As a result, many organizations use the RSS XML data structure as the basis for presenting data. These companies use server-side scripts to generate XML data because scripts allow more control over the data.
The XML data generated by the server-side script can be determined by the parameter value. The value transmitted to the external server is either attached to the end of the URL, which is the HTTP GET method, or provided in the request, which is the HTTP POST method. The HTTP GET method uses a simple query to obtain data, which is a relatively safe method. The HTTP POST method is usually used to send data or instruct an external server to manage data.
Whether you want to view (select in the database), insert, update, or delete data on the external server, you need to configure each command using the data source properties dialog box.
When you create a data connection by using XML files or server-side scripts, you may need to configure the authentication method for accessing XML data. The data source properties dialog box provides four options:
1. does not try to verify. Used when an external server accepts anonymous access, or when the user must provide their username and password.
2. save the user name and password to the data connection. Use this option when the XML data is protected by a password and you want everyone to be able to access the data without entering a username and password. The username and password are transmitted over the network as text, so you may need to contact your IT department to add further infrastructure security.
3. Use Windows authentication. Used when SharePointer 2010 and the XML file are located on the same server.
4. Use single sign-on authentication. At the time of writing this book, although this option is available, it does not work with data sources. If you use this verification method, you need to use ECTs. For more information about external lists and ECTs, please see Chapter 7.
In this exercise, you use a server-side script connection to obtain XML data.
Preparation: Use SharePoint Designer to open the website, DataSourceTest.aspx page and data source library page.
1. In a browser, visit http://technet.microsoft.com.
2. In the search box, type sharepoint designer 2010, and click Enter to display the search results. 
3. In the result line, right-click the RSS icon, and click Copy Link Address.
4. In the new group on the Data Source tab of the Data Source Library page in SharePoint Designer, click the REST Service connection.
5. Right-click and enter the URL to the server-side script, and click Paste.
6. Click to add or modify the parameter list box.
7. On the General tab, enter the name Microsoft TechNet Search 8. Click OK. The Microsoft TechNet Search data connection appears under RSS, REST, and server scripts on the data source library page. 9. Click the DataSourceTest.aspx tab. 10. Click “Click here to select data source” in the PlaceHolderMain area. Select Microsoft TechNet Search and click OK. The data source details task pane displays many project elements. Each item element displays the information returned from the TechNet Search website (search for sharepoint designer 2010).