A method and apparatus for providing streaming data to multiple clients involves the provision of intelligent gateway at the edge of a network. The gateway is designed so that if it receives a request from a second client within the network for a data stream already being supplied to a first client in the network, that data stream is duplicated by the gateway rather than making a second request for the same stream from a server. Multiple such gateways can be combined to form a large load balancing network. An important aspect of the invention is a software interface in the gateway that enables a data packet address type to be changed from unicast to multicast and vice versa.