Socket.MulticastLoopback Property


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Gets or sets a value that specifies whether outgoing multicast packets are delivered to the sending application.

Namespace:   System.Net.Sockets
Assembly:  System (in System.dll)

public bool MulticastLoopback { get; set; }

Property Value

Type: System.Boolean

true if the Socket receives outgoing multicast packets; otherwise, false.

Exception Condition

An error occurred when attempting to access the socket.


The Socket has been closed.

Multicast is a scalable method for many-to-many communication on the Internet. A process subscribes to a multicast address; then, any packets sent by a subscribed process are received by every other process subscribed to the multicast address.

Setting this property on a Transmission Control Protocol (TCP) socket will have no effect.

The following code example demonstrates the use of the MulticastLoopback property.

      static void ConfigureUdpSocket(Socket udpSocket)
	// set the Don't Fragment flag.
	udpSocket.DontFragment = true;
	// Enable broadcast.
	udpSocket.EnableBroadcast = true;

	// Disable multicast loopback.
	udpSocket.MulticastLoopback = false;

	Console.WriteLine("Udp Socket configured:");
	Console.WriteLine("  DontFragment {0}", 
	Console.WriteLine("  EnableBroadcast {0}", 
	Console.WriteLine("  MulticastLoopback {0}", 

.NET Framework
Available since 2.0
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