When overridden in a descendant class, gets or sets a Boolean value that controls whether default credentials are sent with requests.
Assembly: System.Net (in System.Net.dll)
Set this property to true when requests made by this WebRequest object should, if requested by the server, be authenticated using the credentials of the currently logged on user. For client applications, this is the desired behavior in most scenarios. For applications that wish to control the authentication user experience, instead of using this property you would typically set the Credentials property to the credentials of the client on whose behalf the request is made.
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.