Android: How to communicate with windows desktop application?

Could someone give me a basic idea of how to connect an android device to a windows desktop application and communicate with it programatically?

Basically I want my app to sync data between the windows application either through wifi or through USB. How would I go about doing this?

An example is the WO Webcam app in the android market (https://market.android.com/details?id=com.uwebcam&featu开发者_运维技巧re=search_result)

I have no idea how to do this, so any fundamental concepts would be helpful.

In my past I had gone through such app and used Wifi to make sure that my android app and desktop app are in same network. The procedure that I followed goes like this

1. A desktop app that will act as server will obtain its IP.
2. Android app will create a socket connection this ip and using any non used ports.

Note: This is just an idea in real programming there are many things that you have take into account