UDP Issues
-
I have a .NET app on a terminal that communicates with a third-party server. It initializes communications through UDP. First, my app broadcasts. The server gets the message, and sends one back. This works when the terminal has only one NIC. However, some terminals with multiple NICs cannot communicate, while others can. Any ideas?
-
I have a .NET app on a terminal that communicates with a third-party server. It initializes communications through UDP. First, my app broadcasts. The server gets the message, and sends one back. This works when the terminal has only one NIC. However, some terminals with multiple NICs cannot communicate, while others can. Any ideas?
Squiggs wrote:
First, my app broadcasts
AFAIK that means your app sends a broadcast packet through one NIC; how do you make sure you picked the right NIC? Wouldn't it be easier to use TCP/IP and address the server by its name or IP address? :)
Luc Pattyn
Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.
Local announcement (Antwerp region): Lange Wapper? Neen!
-
Squiggs wrote:
First, my app broadcasts
AFAIK that means your app sends a broadcast packet through one NIC; how do you make sure you picked the right NIC? Wouldn't it be easier to use TCP/IP and address the server by its name or IP address? :)
Luc Pattyn
Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.
Local announcement (Antwerp region): Lange Wapper? Neen!
I can not use TCP/IP, because the protocol is not mine. I am interfacing to a third party, of which I have no control. To troubleshoot, I wrote a dummy version of the server. I setup multiple networks. The server sits on one of these. I then connected all of the networks to a 4-port NIC card. No matter how I paired the network cables to the ports on the card, I had no problem communicating. I have only seen this issue at some customer sites. A tech with which I work was at a customer's site today. He saw this problem. When only the network of the server in question was physically connected (or the other adapters were disabled), the software would communicate. However, when other networks were connected, it failed. He was actually able to resolve the issue. The connection to the server was through the on-board NIC. He installed a 4-port NIC on the computer today. When he moved the connection to the server to one of the ports on the new NIC and stopped using the on-board one, everything worked as expected. So, what kinds of network adapter settings in Windows could affect this kind of behavior?
-
I can not use TCP/IP, because the protocol is not mine. I am interfacing to a third party, of which I have no control. To troubleshoot, I wrote a dummy version of the server. I setup multiple networks. The server sits on one of these. I then connected all of the networks to a 4-port NIC card. No matter how I paired the network cables to the ports on the card, I had no problem communicating. I have only seen this issue at some customer sites. A tech with which I work was at a customer's site today. He saw this problem. When only the network of the server in question was physically connected (or the other adapters were disabled), the software would communicate. However, when other networks were connected, it failed. He was actually able to resolve the issue. The connection to the server was through the on-board NIC. He installed a 4-port NIC on the computer today. When he moved the connection to the server to one of the ports on the new NIC and stopped using the on-board one, everything worked as expected. So, what kinds of network adapter settings in Windows could affect this kind of behavior?
Hi, I expect the 4-port NIC to work as one NIC with 4 ports (similar to a router), and not like 4 NICs with 1 port each. So it would reduce the number of (active) NICs in the system. However such can not be the solution as your PCs might have more active NICs, e.g. for wireless LAN. IMO you should enumerate all NICs and either figure out the right one, or broadcast your initial message on each of them yourself (there is the alternative of bridging LANs, turning them all in one big LAN, but I expect that would not be acceptable as it changes things a lot). Enumerating NICs can be done using WMI (class Win32_NetworkAdapter); it would provide information similar to what the IPCONFIG command offers. :)
Luc Pattyn
Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.
Local announcement (Antwerp region): Lange Wapper? Neen!
-
Hi, I expect the 4-port NIC to work as one NIC with 4 ports (similar to a router), and not like 4 NICs with 1 port each. So it would reduce the number of (active) NICs in the system. However such can not be the solution as your PCs might have more active NICs, e.g. for wireless LAN. IMO you should enumerate all NICs and either figure out the right one, or broadcast your initial message on each of them yourself (there is the alternative of bridging LANs, turning them all in one big LAN, but I expect that would not be acceptable as it changes things a lot). Enumerating NICs can be done using WMI (class Win32_NetworkAdapter); it would provide information similar to what the IPCONFIG command offers. :)
Luc Pattyn
Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.
Local announcement (Antwerp region): Lange Wapper? Neen!