A method, system and program for transmitting different quality versions of a stream to end-user nodes of a network. The method comprises: for each of a plurality of possible combinations of versions of the stream to different consuming end-user nodes, evaluating a utility function for each of those consuming end-user nodes, the utility function being dependent on the version and defining a quantitative measure of end-user benefit that would be experienced at the respective end-user node by consumption of the respective version; for each of said plurality of possible combinations of versions of the stream over said routes, determining an overall utility value based on the respective evaluation of the utility functions of each of said plurality of consuming end-user nodes; and selecting a preferred combination of versions of the stream over said routes based on the overall utility values of the different possible combinations.