Abstract: A network is operated such that message forwarding traffic is shared among routers in a load-sharing set. The routers are respectively associated with different non-overlapping subspaces of a source address space from which source addresses of source nodes on the network are drawn, and each router has an identifier uniquely identifying the router in the load-sharing set. Address request messages identifying a predetermined forwarding route are broadcast on the network by source nodes, each request message containing a source address of the broadcasting node. In response to each address request message, each router determines whether the source address is within the address subspace associated with the router, and if so returns the router's identifier to the source node.