US 11,838,198 B2
Path optimization based on reducing dominating set membership to essential parent devices
Pascal Thubert, Roquefort les Pins (FR); Patrick Wetterwald, Mouans Sartoux (FR); Jean-Philippe Vasseur, Saint Martin d'Uriage (FR); and Eric Michel Levy-Abegnoli, Valbonne (FR)
Assigned to Cisco Technology, Inc., San Jose, CA (US)
Filed by Cisco Technology, Inc., San Jose, CA (US)
Filed on Jul. 2, 2020, as Appl. No. 16/919,793.
Application 16/919,793 is a continuation of application No. 15/446,705, filed on Mar. 1, 2017, granted, now 10,749,786.
Prior Publication US 2020/0336406 A1, Oct. 22, 2020
This patent is subject to a terminal disclaimer.
Int. Cl. H04L 45/02 (2022.01); H04L 45/42 (2022.01); H04L 49/25 (2022.01)
CPC H04L 45/02 (2013.01) [H04L 45/42 (2013.01); H04L 49/251 (2013.01)] 20 Claims
OG exemplary drawing
 
16. An apparatus comprising:
a device interface circuit configured for receiving, in a directed acyclic graph (DAG) topology, a membership message from a root of the DAG topology, the membership message identifying the apparatus as a dominating set member belonging to a dominating set of dominating set members limited to only the root and essential parent devices in the DAG topology, wherein all leaf devices in the DAG topology and redundant parent devices in the DAG topology are excluded from the dominating set;
a memory circuit; and
a processor circuit configured for generating an advertisement for transmission by the device interface circuit to the root, the advertisement generated by the processor circuit advertising reachability by the apparatus to one or more other dominating set members;
the device interface circuit further configured for receiving path information for reaching a destination network device in the DAG topology, the path information generated by a path computation element by limiting computation of an optimized path to the dominating set members, the optimized path reaching the destination network device via a selected sequence of essential parent devices, the path information causing the processor circuit to cause forwarding of a data packet, originated by a source network device, toward the destination network device along the optimized path that is distinct from the DAG topology, the optimized path causing the data packet to reach the destination network device without traversing a common parent network device of the source network device and the destination network device, wherein the common parent network device is in the DAG topology and is not the root;
wherein:
the device interface circuit is configured for detecting an advertisement message multicast by a non-dominating set network device in the DAG topology, the advertisement message specifying that the non-dominating set network device can reach the one or more other dominating set members distinct from the network device,
the processor circuit configured for storing in the memory circuit that the one or more dominating set members are reachable via the non-dominating set network device,
wherein the advertising to the root of the reachability by the network device to the one or more other dominating set members is based on the advertisement message detected by the network device.