Abstract: A path discovery process is provided for discovering a lowest cost combination of a plurality of paths from the source node to the destination node via links between pairs of nodes along the paths. A path discovery messages from a source node is forwarded through the network. Prior to forwarding the path discovery message a node tests one or more conditions for disabling the forwarding. Upon receiving an instance of the path discovery message, this may include testing whether no other instance of the path discovery message has both smaller cost and a previous path that contains only nodes that occur also in the path of the received instance. Furthermore, this may include testing whether a destination of the path discovery message was also a node to which a preceding node along the path has a further link, and a cost of the path from the preceding node to the next node via said further link is not larger than the cost of the path from the preceding node to the next node.

Abstract: A system and method are provided for transmitting data via a network. Upon receiving a request for unicast transmission of the data, the system and method respond to the request by i) formatting the data in accordance with a transport protocol to obtain formatted data and ii) providing the formatted data to the network, the formatted data comprising a destination address field. The network is a programmable network comprising one or more forwarding nodes that are remotely controllable. In order to effect a multicasting of the formatted data, the one or more forwarding nodes are controlled to i) replicating the formatted data to obtain replicated formatted data, and ii) setting the destination address field of the replicated formatted data to an address originating from a further request for the unicast transmission of the data. An advantage of the system and method is that multicasting may be provided for ‘off-the-shelf’ unicast receivers.

Abstract: A path discovery process is provided for discovering a lowest cost combination of a plurality of paths from the source node to the destination node via links between pairs of nodes along the paths. A path discovery messages from a source node is forwarded through the network. Prior to forwarding the path discovery message a node tests one or more conditions for disabling the forwarding. Upon receiving an instance of the path discovery message, this may include testing whether no other instance of the path discovery message has both smaller cost and a previous path that contains only nodes that occur also in the path of the received instance. Furthermore, this may include testing whether a destination of the path discovery message was also a node to which a preceding node along the path has a further link, and a cost of the path from the preceding node to the next node via said further link is not larger than the cost of the path from the preceding node to the next node.

Abstract: A system and method are provided for transmitting data via a network. Upon receiving a request for unicast transmission of the data, the system and method respond to the request by i) formatting the data in accordance with a transport protocol to obtain formatted data and ii) providing the formatted data to the network, the formatted data comprising a destination address field. The network is a programmable network comprising one or more forwarding nodes that are remotely controllable. In order to effect a multicasting of the formatted data, the one or more forwarding nodes are controlled to i) replicating the formatted data to obtain replicated formatted data, and ii) setting the destination address field of the replicated formatted data to an address originating from a further request for the unicast transmission of the data. An advantage of the system and method is that multicasting may be provided for ‘off-the-shelf’ unicast receivers.