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Multible programs/instances using the same UDP Port in C#

I am struggling with a bit of network magic and hoped someone would be able to explain me what is happening.
I am trying to reuse udp ports. So if I have multible programs listening on the same udp port i want both of the applications to receive the data send by a different device.
Using the following code I'am able to achive just that:
IPEndPoint localEndoint = new IPEndPoint(IPAddress.Any, 67); //the local endpoint used to listen to port 67
//Create a new UDP Client and bind it to port 67
DhcpSniffer = new UdpClient();
DhcpSniffer.ExclusiveAddressUse = false; //Allow multible clients to connect to the same socket
DhcpSniffer.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true); // Connect even if socket/port is in use
DhcpSniffer.Client.Bind(localEndoint);
DhcpSniffer.Client.ReceiveTimeout = Timeout;
//receive on port 67
dhcpPacket = DhcpSniffer.Receive(ref localEndoint);
Both of my programs can listen to DHCP messages in the network and don't block each other.
Now i want to do the same thing with port 15120 where a RTP video stream is streamed to. However this does not work. I am using the same code but with no success only one application at a time can receive the stream, the other will run in a timeout.
IPEndPoint RemoteIpEndPoint = new IPEndPoint(IPAddress.Any, port);
//Create a new UDP Client and bind it to port 15120
udpReceiver = new UdpClient();
udpReceiver.ExclusiveAddressUse = false; //this is an attempt to receive the stream on mutlible instances...this works for DHCP but not for RTP for some reason....
udpReceiver.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true); // Connect even if socket/port is in use
udpReceiver.Client.ReceiveTimeout = timeout; //set the sockete timeout
udpReceiver.Client.Bind(RemoteIpEndPoint); //bind to the port from any IP
//receive packets on port 15120
Byte[] receiveBytes = udpReceiver.Receive(ref RemoteIpEndPoint);
I hope somebody is able to shine a light on my confusion
Update:
I found out it works with DHCP because it is send to the broadcast IP (255.255.255.255). Now I need to find out how i can change the Socket behaviour to treat my RTP stream as if it was broadcasted so i can see it in two application at the same time. (Yes I could configure my stream-source to broadcast, but this is not the goal of this).
The goal is to reconfigure the Socket to behave as explained. Not to save the stream on a harddrive or redirect it using the local host.

First, its not possible to have multiple programs listen on the same port (As far as I know it's a big security conflict)
What you can do tough, is use a NetworkManager that listen on you port (Lets call it port 8080) who will then redirect the information to you apps ports (App1 could use port 8081 and App2 use port 8082). Either you write your own, using Flask to listen on 8080 and then rerouting the package to localhost:8081 and localhost:8082 could be a simple and fast solution.
Doing this would help you secure the network and you can redirect to as many ports as you need, pretty much like a docker swarm would balance the incoming network to its cluster.

It is not possible with multible programs to access the data from a unicast UDP package, it works only with multicast, there is no "easy" way around this by reconfiguring the UdpClient

C# Socket listener does not bind to port

I try to listen a specific port on server. I write a simple console app but I get error:
Only one usage of each socket address (protocol/network address/port)
is normally permitted.
However, I don't find any process to listening that port. Resource manager and CurrPorts don't show any information.
My code (all code):
var ipEndPoint = new IPEndPoint(IPAddress.Any, 7001);
var tcpListener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
tcpListener.Bind(ipEndPoint);
tcpListener.Listen(100);
My questions are:
How can I find which process listen the port? Currports doesn't show, also resmon too.
Why node.js is listen the port and getting messages? What is different?
I think I have a hidden thread but I doesn't find it. I use ProcessExplorer.
Update:
When I run my console app after server reset, it is working correctly.
However, when close and re-open the app, it is not working and given that exception above.

I believe you have connections to that port which are not completely closed. This prevents the port from being opened again. To solve the problem you have to set the socket option ReuseAddress before binding the port.
var ipEndPoint = new IPEndPoint(IPAddress.Any, 7001);
var tcpListener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
tcpListener.SetSocketOption(SocketOptionLevel.Socket,SocketOptionName.ReuseAddress,true);
tcpListener.Bind(ipEndPoint);
tcpListener.Listen(100);

I run into the same problem with the mysql port 3306. Neither tcpview , netstat -ano nor currports shows anything.
But
netsh interface ipv4 show excludedportrange protocol=tcp
shows that the port is reserved.
It seems hyper-v / docker was the culprit and the fix is to disable hyper-v , reserve the port with
netsh int ipv4 add excludedportrange protocol=tcp startport=<your port> numberofports=1
and reenable hyper-v.
Origin : https://stackoverflow.com/a/54727281/32083 .
More background is here https://github.com/docker/for-win/issues/3171

C# - WireShark detects incomming packets but application does not receive them

I've got a strange problem. I have a client sending packets to my server, but my servers UDP socket never receives them. Same thing happens the other way around, if I send and he tries to receive.
Check this image, captured from wireshark:
http://img263.imageshack.us/img263/2636/bokus.png
I hav bound my UDP socket to EndPoint 192.168.2.3, which is the internal IP of the server, and port 9998.
The client sends data to my IP, which should then be forwarded to the local server machine..
As you can see wireshark clearly detects incomming packets for 192.168.2.3 with destination port 9998 but nothing gets delivered!
(...why does it say distinct32 btw in destination port?)

Something else to watch for is make sure any firewall you might running has a rule setup to allow communications on your port 9998.
If I had to guess (would need to see your recieving C# code to know), It looks like you might be trying to receive UDP packets but using TCP protocol on the client side. (Or i might just be misunderstanding some of the text of your screenshot.)
Theres no need to 'listen' for a connection when using UDP. UDP packets don't have a connect/disconnect protocol. Nor do they guarantee that packets are received in the same order they're sent.
try using something along these lines in your C# client and see if you get data.
var udpClient = new System.Net.Sockets.UdpClient(9998);
Byte[] receiveBytes = udpClient.Receive(ref RemoteIpEndPoint);

Sending a message through a particular client port

I am doing projects in sockets.usually the server listens in a particular port,and the client has to connect to the port then the send and receives will happen.but we don't specify any port number in the client side,but i am in a situation to use a port in a client side, through this port only the messages will delivered to the server.how to do this?
In my client side they are restricting the ports ,so if want use to a valid free port i have to set it in the client program,instead of OS Choosing it.This is my problem.

Bind the client socket to local address (ip and port number) before connecting to server. Be ready to handle errors e.g. when the port is not available (choose next port, retry).

I guess you're using the System.Net.Sockets namespace?
If so, classes like NetworkStream take the Socket as a constructor parameter:
http://msdn.microsoft.com/en-us/library/system.net.sockets.networkstream.aspx
Similarly, the TcpClient takes Port and Server as constructor arguments, Port is the same as socket in this context:
http://msdn.microsoft.com/en-us/library/system.net.sockets.tcpclient.aspx
Finally. you can control the number of this socket in a few ways:
Command Line Parameter
Setting in an Application.Config file
Read it from the Registry
There are a few methods for this type of thing.

Find Out Connected clients IP's?

How to find out Connected Clients Ip Address. And how we can store that address to an array of datatype IPAddress?

Check the RemoteEndPoint of your socket:
If you are using a connection-oriented
protocol, the RemoteEndPoint property
gets the EndPoint that contains the
remote IP address and port number to
which the Socket is connected. If you
are using a connectionless protocol,
RemoteEndPoint contains the default
remote IP address and port number with
which the Socket will communicate. You
must cast this EndPoint to an
IPEndPoint before retrieving any
information. You can then call the
IPEndPoint.Address method to retrieve
the remote IPAddress, and the
IPEndPoint.Port method to retrieve the
remote port number.
If you use higher level components like TcpListener and TcpClient then you can access the underlying socket and retrieve the remote end point.
If you use other technologies like ASP.Net, WCF or Remoting then you must say so in your post.
To store an IPAddress you retrieve the underlying bytes using IPAddress.GetAddressBytes. You reconstruct the address from the bytes using the byte[] constructor.

Are we in Windows? Do you need to use this information inside an application or a console command could do the trick?
maybe you could try with netstat -na in a shell.