frontline

[ I know nothing about LAN, yet. ]

Hi, I really hope somebody can help me.

Recently my dad got a router and hooked up LAN, we have 2 pcs running on the LAN (his downstairs(main), and mine upstairs).

I have been making a remote administration tool, it's basicly a server which listens for connections on my computer and a client which is on somebody elses computer (not in the lan) which connects to the client. The program is actualy a simple chat client.

It was working fine before, but since we have got LAN it doesnt work at all! the client on the remote computer cant connect to mine!

I tried the IP i get from whatsmyip.com and have the client connect to it and nothing , doesnt work.

Anybody know what the problem is ? if you need any more info just ask

Thanks

hotshot

Welcome to the PC Guide forums!

Your router's LAN changes the address scheme to something other than the WAN address your ISP assigned to your account.
Example:
LAN: 192.168.1.xxx
WAN 88.xxx.xxx.xxx

A VPN (Virtual Private Network) is one way to get through that translation and make the connection, assuming you have a static address assigned by your ISP.
Remote Desktop is another way to do administration, are both systems using XP?

frontline

ok ..........

hotshot

You need to open the chat programs port range in the router. When you establish a connection from one application to another they negotiate which port to use. Those ports may need to be opened in the router, it is sometimes called a pinhole. Because you are allowing a small number of ports access.

frontline

Well the port I choose to use is 5051

The client on one computer listens on that port, the server on the other computer connects to the ip on that port.

I have tried "port fowarding" and still nothing!

hotshot

You can't have just one port think of it as traffic. You cannot send and recieve on the same road. Also, there is different kinds of protocols, essentially it is either connection or connectionless. TCP or UDP. Likely you need to install a packet sniffer like Ethereal and start up the application. Watch what traffic is sent out. Do the same on the server side. This will help you figure out what the application is doing and make it easier to understand which traffic to allow through the router. If you can, you could run a packet sniffer on both machines and connect them via a crossover cable or through a hub. In 30 seconds of monitoring you would know just about everything you need to know.

frontline

You have three choices:

1) A VPN
2) Open the ports outside of the routers security
3) Port forward the requests to your local IP address....

hotshot

there is one way. some routers have a DMZ that you can assign. it means your computer will be the one associated with that ip address. there may be some routing needed but, i would use this as a last resort.

My housemate has a DynDNS account, and for me to access his computer (FTP) from work, he had to set up dyndns on the router, then put his machine in the DMZ, and make sure his IP was static on the network. If your chat program only uses ip addresses, you wont need a dyndns account.

But like i said, your machine will be exposed to the internet.

frontline

If you go into the DMZ, you are outside of the routers protection. A last resort for sure.

hotshot

All he needs to do is allow the right ports access through his router.