I make a TCP/IP server in C# and client too. TCP-server is broadcasting packets to clients.
But it only broadcast on local IP not on other computers/machines.
All computers on connected SN MP server. I also changed IP address in code from (127.0.0.0) to network IP address (SNMP server IP Address). I pinged others IP with my computer; it's working but not making a connection with my TCP-server that I have made in C#.
Can you help me in this scenario?
Can't give a proper answer without seeing some code, but for starters, you can check whether the port is blocked in firewall or something (try to allow incoming connections in firewall for the specific port (whitelist it) )
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I have a synchronous TCP server and client application the works absolutely fine on two separate host machines.
What I'd like to know is what IP and port do I bind the server socket and the client socket to when the applications are both running on the same host machine.
I can't find any solid information on Google about this.
When I try and use my network IP which was 192.168.0.32 I get an error that says the Host actively refused the connection.
I cannot find any reasonable information about this error.
Can I listen and send on the same Port?
What IP address should I use to bind the server and the client, when both applications are running on the same machine?
Thanks for your time.
In order to run both client and server applications on the same host you should bind your server socket to localhost (you can actually write "localhost" it's a preserved word or 127.0.0.1 ) and address it from the client as well.
Localhost allways refers to the computer you work on.
If you'd like to access your server from a machine which is outer to your local network using your network ip you've mentioned, you should first search for "IP FORWARDING" option in your router settings and forward incomming requests to the machine where the server is running on.
Or (my favourite) use the great IP TUNNELING service of ngrok. You can find it here https://ngrok.com/
good luck.
So the answer to this question is that I must bind to my loop back address with separate ports for the client and the server !!
The IP address could be the loopback 127.0.0.1 for both, or your IP address, I don't see why it would not work.
The port on the other hand has to be the same for it to work, assuming the client application doesn't also listens to the port that you "bind" it to.
You have to tell the server on which port it should listen. The client then has to send data on the same port for the server to get the information.
This example should get you going: https://www.codeproject.com/Articles/1415/Introduction-to-TCP-client-server-in-C
The Tcp client/server code I'm working with is here: client and server.
As the title goes, I'm running the server code on my computer and I want to connect to it from another device using the client code. My question is, to what ip address does my client code have to connect? I know there are many related posts, but I'm only getting information on what's wrong rather than the solution.
This is a common problem when developing client/server applications. In a typical home network, there are multiple local IP addresses and a single external IP address. All devices communicating with your network from the outside must use the external IP address. However, when writing client/server applications, if you simply input the external IP address as the address to connect to, you'll quickly discover this won't work.
You need to use Port Forwarding. The client and server will be communicating over a specific port, and Port Forwarding is how your router knows which local IP address to send data to when the client is connecting to the external IP address. You want to login to your router settings, navigate to the section regarding Port Forwarding, and specify that communication over the port you're using in your server should be redirected to the local IP address that your server is running on. Exactly how to change these settings on your router depends on which router you're using.
Run the ipconfig command in a Windows Command Prompt on the machine running your server. Obtain the local IPv4 address from the results. This is the address to use when Port Forwarding the port used by your client/server applications. Adjust your router settings accordingly, and then your client should be able to use your external IP address just fine.
To find your external IP address, any website such as http://www.whatsmyip.org/ should work fine.
If you want to avoid all of these problems for now and simply test your application on your home network, then use the local IPv4 address found when running the ipconfig command on the machine your server is running on. Note that this will only work if both the client and server are running on the same network.
I can not connect to the TCP Server when i am on a different network
I am trying to connect to a Tcp server I created on another network, I have had no luck. Is there a way to do this?
What is is the IP Address that i need to put in to the Client program?
The server works fine if you are on the network but how do i connect is i am on a different network?
I have tried to connect with the external IP Address but the message just sat at the router, how do i make the router send the message to my PC?
What am i doing wrong
How do i fix it
Your TCP server should be on a system with a public(external) ip address. Clients then will be able to connect to the server even if they are inside a LAN. Note that the ip adresses in a LAN are different from external ip-addresses. The translation is called NAT.
So because your server runs on a computer inside a LAN it will not be accessible for other computers on the internet. Your router on the other hand has a public ip address which will be accessible from the internet. You can configure your router to forward a port to your computer so that your router connects your server with the internet. Note that port forwarding is often a bad security practice. Make sure that you pick a port number that's not used by any other program.
Also keep in mind that the TCP traffic from the client to the server is probably un-encrypted. This means that your traffic will be vulnerable for man-in-the-middle attacks. You should try to establish an connection which uses SSL. (Note: SSL is not equal to https) For more information please look at the OSI-model.
I am using a code to know the client ip, who is logged in to my website up to this it is working fine, but if the client blocks their ip then what I will get, will I get their ip, and actually is there any chance to block their ip in the internet connection?
Please help me, Thanks in advance
It is not possible to block an IP address from the webserver. Ultimately, the TCP/IP connection has to know the address of both ends that are communicating.
This doesn't mean that the IP address that you see on the server is actually the IP address of the client, any more than it means the IP address of the server is the IP address that the client actually tried to reach.
If the client machine is behind a proxy or NAT device, you will see the IP address of the proxy or whatever IP address the NAT device is using for the specific TCP/IP session.
You cannot assume that HTTP requests from the same IP address are associated with the same browser, machine or user.
No. There is no possibility..
If anybody want to access your website , should be need to internet connection..
To connect in internet , each connection unique IP address
You will get the IP but not necessarily the IP of the client machine. Some time firewall block the actual IP address of the machine and provide the same IP of the node inside the Firewall
I wanted to learn how networking in c# works, so I learned how to use TCP server and clients.
The only problem is that it's working only if both computers are connected to the same network..
How can I make them communicate even if they aren't?
TCP/IP sockets should work between any two end points as long as there is a route between them. If there is no route between them then you are talking about a case where there are two separate disconnected networks. In that case you will need something to bridge the two networks.
If you are using TCP/IP server/client communication and the computers are on different networks that has a route connecting them and they cannot communicate then you should look at firewall settings and other network settings to make sure TCP/IP packets from one network are able to reach the other network.
Make sure you are using the correct IP address when the client tries to connect to the server. If you have a server at IP address 10.0.0.5 listening on port 4823 try to telnet to that IP address from the client using the server IP address 10.0.0.5 and port 4823. If it connects that usually means that you have things set up right.
From a command prompt: telnet 10.0.0.5 4823
Communication in TCP is done with IP addresses. So even if the client and the server are not on the same network if you specify the IP address of the server, the client will be able to communicate with it (assuming of course the network that the client resides on is configured properly and knows how to reach the server's network). You could also use the DNS service and provide the FQDN of the server instead of an IP address. The DNS server on the client network will resolve the server's FQDN to an IP address.