Media transport protocol selection

A method and network node for distributing media across an IP network, the network node having multicast and peer-to-peer ingress interfaces, and unicast and peer-to-peer egress interfaces. For each of a plurality of contents, the network node selects an ingress interface and receives media packets representing the content at the selected interface. For each media packet received, the network node determines from information conveyed in the media packet whether that media packet can be cached at the network node and caches the media packet if permitted. When the network node receives a request from a further network node for a given content, the network node selects an egress interface and forwards media packets representing the given content to the further network node over that selected interface. If media packets representing the given content were cached, the cached media packets are forwarded to the further network node.