A system and method for managing a server in a packet data network. A transport protocol session is established between a client (20) and server (14_1) to transfer content from the server to the client in data packets. The transport protocol path is assigned an n-tuple identifier, whereupon the server transmits to the client data packets with the n-tuple identifier. The server additionally transmits declarative information as signaling packets with the n-tuple identifier, wherein the declarative information includes an identifier which is specific to the data being transmitted in the ongoing session. This allows other servers (14_2) to receive the signaling packets and detect the data that is being transmitted. If such another server then determines that it also has the same data and is better placed to serve that data to the client, it can offer to take over the session.