how to access a web service on a server with non-static IP?

Hi!

I found most silverlight examples access a web service like this:
factory.CreateChannel(new EndpointAddress("http://(IP of the server):19021/Service1.svc"))
But if my server doesn't have a static IP,  how to let silverlight know the server IP or use a config file to make it? It's not wise to recompile it every time I change the IP, right? :P

Thanks~

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