An overlay network node is arranged to provide robust reply routing for requests and replies travelling over the network. Each node comprises first means which forwards each request originating in a source node and destined for destination node. The node comprises second means which redirect replies if the node from which the corresponding requests were received is no long accessible. The reply is, for example, turned into a request containing the reply as its payload and is returned towards the source node according to the rules used for forwarding the requests.