How to use ReceiveFrom to capture multicast data

[Nuno Magalhaes]

The MSDN says that I have to bind the socket on a local address to use
ReceiveFrom function. How can I bind the socket on a multicast address
in order to get the multicast data.
Say that I want to receive data that is sent from 10.154.0.104:55 4 to
224.1.2.3:554.
How can I get the data at 224.1.2.3:554 since this is a multicast
address, and using ReceiveFrom? Where do I bind my socket (I have to
bind it to a local IP otherwise gives invalid address)?

Thanks.

--------------------------

Here's a simple code that blocks:

public MulticastServer (int localPort)
{
socket=new
Socket(AddressF amily.InterNetw ork,SocketType. Dgram,ProtocolT ype.Udp);
IPHostEntry IPHost=Dns.GetH ostByName(Dns.G etHostName());
IPAddress ip=IPAddress.Pa rse(IPHost.Addr essList[0].ToString());
IPEndPoint ep=new IPEndPoint(ip,l ocalPort);
socket.Bind(ep) ;
}

public byte[] ReceiveFrom(str ing ipAddress,int port)
{
//if(socket.Avail able==0)return null;
IPEndPoint ep=new IPEndPoint(IPAd dress.Any,0);
EndPoint ep2=(EndPoint)e p;
byte[] buffer=new byte[1500];
int receivedBytes=s ocket.ReceiveFr om(buffer,ref ep2);
byte[] packet=new byte[receivedBytes];
Array.Copy(buff er,0,packet,0,r eceivedBytes);
return packet;
}