Unicast UDP Server

[O.B.]

I'm attempting to set up at UDP server in unicast mode, where
10.1.16.25 is the remote machine. Below is the error being thrown
when binding the socket. What am I doing wrong?

System.Net.Sockets.SocketException
"The requested address is not valid in its context"
Socket socket = new Socket(AddressFamily.InterNetwork,
SocketType.Dgram,
ProtocolType.Udp);

socket.SetSocketOption(
SocketOptionLevel.Socket,
SocketOptionName.ReceiveBuffer,
75000000); // 75 MB

socket.SetSocketOption(
SocketOptionLevel.Socket,
SocketOptionName.SendBuffer,
1472);

EndPoint receiveEndPoint = new IPEndPoint(
System.Net.IPAddress.Parse("10.1.16.25"),
socketConfig.Port);

socket.Bind(receiveEndPoint);

[Peter Duniho]

On Thu, 27 Mar 2008 19:07:05 -0700, O.B. <fu******@bellsouth.netwrote:

I'm attempting to set up at UDP server in unicast mode, where
10.1.16.25 is the remote machine. Below is the error being thrown
when binding the socket. What am I doing wrong?

You're trying to bind your local socket to a remote address.

If you want to specify a remote address to be used as the default
destination for the UDP socket, use Connect(), not Bind().

By the way...IMHO, you shouldn't be messing with the socket buffer sizes
unless you have already gotten everything else working, you know exactly
what you're doing, _and_ you have run into some problem that requires you
to change the default buffer sizes.

Pete

[O.B.]

On Mar 27, 10:07 pm, "Peter Duniho" <[e-mail]>
wrote:

On Thu, 27 Mar 2008 19:07:05 -0700, O.B. <[e-mail]:

I'm attempting to set up at UDP server in unicast mode, where
10.1.16.25 is the remote machine. Below is the error being thrown
when binding the socket. What am I doing wrong?

You're trying to bind your local socket to a remote address.

If you want to specify a remote address to be used as the default
destination for the UDP socket, use Connect(), not Bind().

But that would require the remote connection to be Bound to that port
to accept connections. Here is the dilemma. We have a user that has
other commercial software that is only capable of running their
sockets as client UDP broadcast connections on a fixed port. On our
end, the user wants the ability to open two UDP servers both on the
same port, but for each one to filter based on the IP that is sending
data. I was hoping that it would be possible to do this in the
connection setup rather than having our asynchronous receive callback
do the filtering.

With that said, what is the point of binding to a specific address if
it isn't allowed?

By the way...IMHO, you shouldn't be messing with the socket buffer sizes
unless you have already gotten everything else working, you know exactly
what you're doing, _and_ you have run into some problem that requires you
to change the default buffer sizes.

We started off with defaults and lost too many packets. 75 MB ended
up being a good number. Most of our machines are running with 4 GB or
more of memory, so it isn't an issue.

[Peter Duniho]

On Sat, 29 Mar 2008 20:59:59 -0700, O.B. <fu******@bellsouth.netwrote:

Each time the receive callback is invoked, the code checks to see how
full the buffer is. When it is close to 100%, we start noticing data
not being received.

How do you check to see how full the buffer is?

Yes, it does happen. However, when more than 25% of the packets are
getting lost, we start looking at the network for issues.

25% is high, yes. Still, that doesn't mean that it's simply a buffer size
issue.

Thanks again for your help. I think we're good to go for now.

Somehow I suspect not. But if you're satisfied with the solution, I guess
that's your perogative. Good luck.

Pete

[O.B.]

On Mar 29, 7:08 pm, "Peter Duniho" <[e-mail]>
wrote:

On Sat, 29 Mar 2008 20:59:59 -0700, O.B. <[e-mail]:

Each time the receive callback is invoked, the code checks to see how
full the buffer is. When it is close to 100%, we start noticing data
not being received.

How do you check to see how full the buffer is?

Yes, it does happen. However, when more than 25% of the packets are
getting lost, we start looking at the network for issues.

25% is high, yes. Still, that doesn't mean that it's simply a buffer size
issue.

Thanks again for your help. I think we're good to go for now.

Somehow I suspect not. But if you're satisfied with the solution, I guess
that's your perogative. Good luck.

Pete

Well, doing a Socket.Connect() on a UDP socket causes a Socket.Bind()
to throw a socket exception. So it is not possible to Bind on a local
address in UDP *and* use Connect to specify a remote address at the
same time. Oh well ... that's life.