The System.Net namespace provides a simple programming interface for many of the protocols used on networks today. The WebRequest and WebResponse classes form the basis of what are called pluggable protocols, an implementation of network services that enables you to develop applications that use Internet resources without worrying about the specific details of the individual protocols.

	Class	Description
	AuthenticationManager	Manages the authentication modules called during the client authentication process.
	Authorization	Contains an authentication message for an Internet server.
	Cookie	Provides a set of properties and methods that are used to manage cookies. This class cannot be inherited.
	CookieCollection	Provides a collection container for instances of the Cookie class.
	CookieContainer	Provides a container for a collection of CookieCollection objects.
	CookieException	The exception that is thrown when an error is made adding a Cookie to a CookieContainer.
	CredentialCache	Provides storage for multiple credentials.
	Dns	Provides simple domain name resolution functionality.
	DnsPermission	Controls rights to access Domain Name System (DNS) servers on the network.
	DnsPermissionAttribute	Specifies permission to request information from Domain Name Servers.
	DownloadDataCompletedEventArgs	Provides data for the DownloadDataCompleted event.
	DownloadProgressChangedEventArgs	Provides data for the DownloadProgressChanged event of a WebClient.
	DownloadStringCompletedEventArgs	Provides data for the DownloadStringCompleted event.
	EndPoint	Identifies a network address. This is an abstract class.
	EndpointPermission	Defines an endpoint that is authorized by a SocketPermission instance.
	FileWebRequest	Provides a file system implementation of the WebRequest class.
	FileWebResponse	Provides a file system implementation of the WebResponse class.
	FtpWebRequest	Implements a File Transfer Protocol (FTP) client.
	FtpWebResponse	Encapsulates a File Transfer Protocol (FTP) server's response to a request.
	GlobalProxySelection	Contains a global default proxy instance for all HTTP requests.
	HttpListener	Provides a simple, programmatically controlled HTTP protocol listener. This class cannot be inherited.
	HttpListenerBasicIdentity	Holds the user name and password from a basic authentication request.
	HttpListenerContext	Provides access to the request and response objects used by the HttpListener class. This class cannot be inherited.
	HttpListenerException	The exception that is thrown when an error occurs processing an HTTP request.
	HttpListenerPrefixCollection	Represents the collection used to store Uniform Resource Identifier (URI) prefixes for HttpListener objects.
	HttpListenerRequest	Describes an incoming HTTP request to an HttpListener object. This class cannot be inherited.
	HttpListenerResponse	Represents a response to a request being handled by an HttpListener object.
	HttpVersion	Defines the HTTP version numbers that are supported by the HttpWebRequest and HttpWebResponse classes.
	HttpWebRequest	Provides an HTTP-specific implementation of the WebRequest class.
	HttpWebResponse	Provides an HTTP-specific implementation of the WebResponse class.
	IPAddress	Provides an Internet Protocol (IP) address.
	IPEndPoint	Represents a network endpoint as an IP address and a port number.
	IPHostEntry	Provides a container class for Internet host address information.
	IrDAEndPoint	Represents an end point for an infrared connection.
	NetworkCredential	Provides credentials for password-based authentication schemes such as basic, digest, NTLM, and Kerberos authentication.
	OpenReadCompletedEventArgs	Provides data for the OpenReadCompleted event.
	OpenWriteCompletedEventArgs	Provides data for the OpenWriteCompleted event.
	ProtocolViolationException	The exception that is thrown when an error is made while using a network protocol.
	ServicePoint	Provides connection management for HTTP connections.
	ServicePointManager	Manages the collection of ServicePoint objects.
	SocketAddress	Stores serialized information from EndPoint derived classes.
	SocketPermission	Controls rights to make or accept connections on a transport address.
	SocketPermissionAttribute	Specifies security actions to control Socket connections. This class cannot be inherited.
	UploadDataCompletedEventArgs	Provides data for the UploadDataCompleted event.
	UploadFileCompletedEventArgs	Provides data for the UploadFileCompleted event.
	UploadProgressChangedEventArgs	Provides data for the UploadProgressChanged event of a WebClient.
	UploadStringCompletedEventArgs	Provides data for the UploadStringCompleted event.
	UploadValuesCompletedEventArgs	Provides data for the UploadValuesCompleted event.
	WebClient	Provides common methods for sending data to and receiving data from a resource identified by a URI.
	WebException	The exception that is thrown when an error occurs while accessing the network through a pluggable protocol.
	WebHeaderCollection	Contains protocol headers associated with a request or response.
	WebPermission	Controls rights to access HTTP Internet resources.
	WebPermissionAttribute	Specifies permission to access Internet resources. This class cannot be inherited.
	WebProxy	Contains HTTP proxy settings for the WebRequest class.
	WebRequest	Makes a request to a Uniform Resource Identifier (URI). This is an abstract class.
	WebRequestMethods	Container class for WebRequestMethods.Ftp, WebRequestMethods.File, and WebRequestMethods.Http classes. This class cannot be inherited
	WebRequestMethods.File	Represents the types of file protocol methods that can be used with a FILE request. This class cannot be inherited.
	WebRequestMethods.Ftp	Represents the types of FTP protocol methods that can be used with an FTP request. This class cannot be inherited.
	WebRequestMethods.Http	Represents the types of HTTP protocol methods that can be used with an HTTP request.
	WebResponse	Provides a response from a Uniform Resource Identifier (URI). This is an abstract class.

Interfaces

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	Interface	Description
	IAuthenticationModule	Provides the base authentication interface for Web client authentication modules.
	ICertificatePolicy	Validates a server certificate.
	ICredentialPolicy	Defines the credential policy to be used for resource requests that are made using WebRequest and its derived classes.
	ICredentials	Provides the base authentication interface for retrieving credentials for Web client authentication.
	ICredentialsByHost	Provides the interface for retrieving credentials for a host, port, and authentication type.
	IWebProxy	Provides the base interface for implementation of proxy access for the WebRequest class.
	IWebProxyScript	Provides the base interface to load and execute scripts for automatic proxy detection.
	IWebRequestCreate	Provides the base interface for creating WebRequest instances.

Delegates

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	Delegate	Description
	AuthenticationSchemeSelector	Selects the authentication scheme for an HttpListener instance.
	BindIPEndPoint	Represents the method that specifies a local Internet Protocol address and port number for a ServicePoint.
	DownloadDataCompletedEventHandler	Represents the method that will handle the DownloadDataCompleted event of a WebClient.
	DownloadProgressChangedEventHandler	Represents the method that will handle the WebClient.DownloadProgressChanged event of a WebClient.
	DownloadStringCompletedEventHandler	Represents the method that will handle the DownloadStringCompleted event of a WebClient.
	HttpContinueDelegate	Represents the method that notifies callers when a continue response is received by the client.
	OpenReadCompletedEventHandler	Represents the method that will handle the OpenReadCompleted event of a WebClient.
	OpenWriteCompletedEventHandler	Represents the method that will handle the OpenWriteCompleted event of a WebClient.
	UploadDataCompletedEventHandler	Represents the method that will handle the UploadDataCompleted event of a WebClient.
	UploadFileCompletedEventHandler	Represents the method that will handle the UploadFileCompleted event of a WebClient.
	UploadProgressChangedEventHandler	Represents the method that will handle the UploadProgressChanged event of a WebClient.
	UploadStringCompletedEventHandler	Represents the method that will handle the UploadStringCompleted event of a WebClient.
	UploadValuesCompletedEventHandler	Represents the method that will handle the UploadValuesCompleted event of a WebClient.

Enumerations

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	Enumeration	Description
	AuthenticationSchemes	Specifies protocols for authentication.
	DecompressionMethods	Represents the file compression and decompression encoding format to be used to compress the data received in response to an HttpWebRequest.
	FtpStatusCode	Specifies the status codes returned for a File Transfer Protocol (FTP) operation.
	HttpRequestHeader	The HTTP headers that may be specified in a client request.
	HttpResponseHeader	The HTTP headers that can be specified in a server response.
	HttpStatusCode	Contains the values of status codes defined for HTTP.
	NetworkAccess	Specifies network access permissions.
	SecurityProtocolType	Specifies the security protocols that are supported by the Schannel security package.
	TransportType	Defines transport types for the SocketPermission and Socket classes.
	WebExceptionStatus	Defines status codes for the WebException class.