Hi,
I have following questions,
1. I want to know that what is the difference between tcp tunneling and regular tcp client server chat program.
2. If I live in Sri Lanka, and I want to connect and pass data to a pc with a dynamic ip (a standalone one, not a server) in India how I do it using tcp tunnel ?

Thank you..

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Tunneling usually involves connecting to one machine on an open port and that machine forwards your data to a third machine on a different port. For example, lets say you want to connect to a chat server that uses port 7000 to communicate with. But you are at work, and they don't allow access through port 7000, but they do allow web browsing (port 80). So you set up on your home machine a TCP tunnel that accepts connections on port 80 and forwards them to the chat server (on port 7000). What it gets back it returns on port 80 to your original machine.

As for your second question, you need to know the ip address of the machine to connect to it. If it is dynamic, there are dynamic DNS servers (some free) that you can use.

Tunneling usually involves connecting to one machine on an open port and that machine forwards your data to a third machine on a different port. For example, lets say you want to connect to a chat server that uses port 7000 to communicate with. But you are at work, and they don't allow access through port 7000, but they do allow web browsing (port 80). So you set up on your home machine a TCP tunnel that accepts connections on port 80 and forwards them to the chat server (on port 7000). What it gets back it returns on port 80 to your original machine.

As for your second question, you need to know the ip address of the machine to connect to it. If it is dynamic, there are dynamic DNS servers (some free) that you can use.

Thanks for the reply..
Can u please give me some examples on using dynamic DNS servers on particular operation ?

check this site out:

http://www.dyndns.org

You can run a client program on each PC to associate the dynamic IP address with a specified host name.

Most routers have an option in the administration tool that will automatically update your dynamic dns account (for example with dyndns.org) any time your external IP changes from your ISP. I use this, in conjunction with specific port forwarding rules on my router, to access the different computers I need to on my home network when I'm not at home.

For example, I've set up www.myURL.dyndns.org:4557 to connect to my web server (local port 80) and www.myURL.dyndns.org:5776 to connect to my SSH server (local port 22). So now I can connect to virtually any service on my home network from anywhere.

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