Is there a rosnetwork? Or similar?

edit

Ros already provides a network transparent communication protocol based on sockets. Normally, you write nodes that directly communicate with the Robot's hardware and publish the data directly via topics.

If your robot data is provided on a socket, I suggest to create a ROS node that uses whatever you are used to, e.g. libc's socket functions, to communicate with your robot. Your ros node then needs to decode the data from the socket, put it into a ros message and publish it. I don't know about any generic way for implementing such a bridge since it is highly specific for your socket based protocol and the ros messages to be published.