A method and computer program product for controlling data transfer between a client device and auxiliary robot cell functions of a robot cell as well as to an interface arrangement for the robot cell. The arrangement includes a reverse proxy providing connectivity for a client device to auxiliary robot cell functions accessible via a local addressing space, where the reverse proxy receives, in a first message having a destination address belonging to the interface device and being a first global address in a global addressing space, a request intended for an auxiliary robot cell function, converts the first address to a first local address of the auxiliary robot cell function in the local addressing space and sends the request to a web server associated with the auxiliary robot cell function using the first local address.