fixed IP,winsock remoteport Q?

Hi,

We use the remotehost property for connecting server.But if we want to do simple application for file sharing with some friends on the net , the app must be client-server , both... For this reason the IP adress of applications must be fixed for connecting , is that so? . Or how can we make a connection with changeable IP adress? , only network adapter adress is being fixed . How can I connect automatically when the other user is online ? How can I find the users IP ?, I don’t want an example , only need general view or some information about this...Thanks.

One would be dns. or a place on the web where it says who is online and what is his IP address. Lets say that you have www.myserver.com
place a file there with all the users that are logged in now you have a list on your system with your buddies and this will only look for your buddies and give you their new ip address, but it needs to be a place that never changes. So i think a static ip is needed and not needed. There is many ways. This might not be the most efficient.