US 8,804,724 B2 · Efficient multicast in a smart grid

Abstract

In a wireless and/or power line communication (PLC) network environment, techniques for multicast of data and management of multicast groups assist in regulating bandwidth consumption and provision of desired multicast data. Nodes indicate interest in multicast groups by transmission of reports upstream. Report transmission may be suppressed to balance bandwidth with need for multicast data. Multicast data packets may be retransmitted downstream to fulfill requests indicated by the reports at a rate and/or frequency based on multicast packet duplication or redundancy. Information, such as broken links or “leave” packets, may indicate that one or more downstream nodes should be removed from a forwarding state. However such removal may impact other nodes. A query may be transmitted downstream, to determine if retransmission/forwarding of multicast retransmissions should continue. Query transmission may be based on a balance between query bandwidth consumption and the needs of downstream nodes.

Claims20

Dependent claims

A method of operating a node, comprising:

under control of circuitry of the node configured to execute the method:
identifying a particular multicast group to join, based on input from an application running on the node;
configuring a multicast report, the multicast report including the particular multicast group indicated by the input;
periodically refreshing the multicast report to include groups of interest to applications running on the node;
overhearing multicast reports sent by nodes within transmission range of the node;
and
periodically transmitting the multicast reports according to a frequency of transmission that is based on a number of the overheard multicast reports that request to join multicast groups indicated by the periodically transmitted multicast report.

4 more elements

Circuitry for operating a node, the circuitry configured to perform acts comprising:

measuring a number of copies of a multicast data packet overheard during a period of time;
retransmitting the multicast data packet at least once if indicated by a multicast forwarding state of the node, the forwarding state indicating need to forward multicast data;
and
retransmitting the multicast data packet a number of additional times based on the number of copies of the multicast data packet overheard during the period of time.

1 more element

One or more non-transitory computer-readable media storing computer-executable instructions that, when executed, cause one or more processors to perform acts comprising:

receiving information at a node including a leave packet or evidence of a broken link associated with a node downstream of the node;
sending a query to other nodes downstream of the node, the query sent in response to the received information and asking for a report of desired groups associated with multicast data;
transmitting subsequent queries according to a rate based on a density of multicast receivers and multicast forwarders that are downstream from the node;
and
expiring the multicast forwarding state in the node if a period of time following the query, or the subsequent queries, exceeds a threshold without receipt of a report, the expiring of the forwarding state indicating that there is no need to forward multicast data for a multicast group.

2 more elements

Dependencies are inferred from the claim text.

Efficient multicast in a smart grid

Life of this patent

Efficient multicast in a smart grid

Life of this patent

Abstract

Claims20