Techniques for distributing information using multicast subsets

A method for receiving data in a packet-switched communications network, comprising the steps of:

• receiving at a particular network node from an adjacent network node that communicates without an intervening network node, subset definition data that indicates which network nodes belong to which subset of a plurality of subsets of network nodes wherein each subset of the plurality of subsets includes a plurality of network nodes;
• determining a particular subset identifier associated with the particular router based on the subset definition data;
• receiving, in a multicast data packet, subset identifier data that indicates a first subset identifier for a first subset of the plurality of subsets;
• determining whether to process the multicast data packet based on whether the first subset identifier matches the particular subset identifier;
• determining a transport cost to each adjacent network node of the adjacent network nodes;
• determining a range of transport cost for each subset of the plurality of subsets;
• determining whether a first transport cost of a first adjacent network node is in a first range associated with a first subset of the plurality of subsets, and if the first transport cost is in the first range, then including the first adjacent network node in the first subset;
• determining a maximum number N of adjacent network nodes included in anyone subset based on a size of an identifier for an adjacent network node and a maximum size of a data packet for the interface on the particular network node;
• and
• including no more than N adjacent network nodes in any subset of the plurality of subsets.

An apparatus for determining a route in a packet-switched communications network, comprising:

• means for determining a plurality of subsets of adjacent network nodes of a packet-switched communications network, which adjacent network nodes communicate without intervening network nodes with a particular network node through an interface on the particular network node, wherein each subset of the plurality of subsets includes a plurality of adjacent network nodes;
• means for sending from the particular network node, through the interface, subset definition data that indicates which adjacent network nodes belong to which subset of the plurality of subsets;
• means for sending data for fewer than all adjacent network nodes in all subsets of the plurality of subsets by including, in a multicast data packet sent over the interface with a multicast destination address, subset identifier data that indicates a particular subset of the plurality of subsets;
• means for determining a transport cost to each adjacent network node of the adjacent network nodes;
• means for determining a range of transport cost for each subset of the plurality of subsets;
• means for determining whether a first transport cost of a first adjacent network node is in a first range associated with a first subset of the plurality of subsets, and if the first transport cost is in the first range, then including the first adjacent network node in the first subset;
• means for determining a maximum number N of adjacent network nodes included in anyone subset based on a size of an identifier for an adjacent network node and a maximum size of a data packet for the interface on the particular network node;
• and
• means for including no more than N adjacent network nodes in any subset of the plurality of subsets.

An apparatus for determining a route in a packet-switched communications network, comprising:

• means for receiving at a particular network node from an adjacent network node that communicates without an intervening network node, subset definition data that indicates which network nodes belong to which subset of a plurality of subsets of network nodes wherein each subset of the plurality of subsets includes a plurality of network nodes;
• means for determining a particular subset identifier associated with the particular router based on the subset definition data;
• means for receiving, in a multicast data packet, subset identifier data that indicates a first subset identifier for a first subset of the plurality of subsets;
• means for determining whether to process the multicast data packet based on whether the first subset identifier matches the particular subset identifier;
• means for determining a transport cost to each adjacent network node of the adjacent network nodes;
• means for determining a range of transport cost for each subset of the plurality of subsets;
• means for determining whether a first transport cost of a first adjacent network node is in a first range associated with a first subset of the plurality of subsets, and if the first transport cost is in the first range, then including the first adjacent network node in the first subset;
• means for determining a maximum number N of adjacent network nodes included in anyone subset based on a size of an identifier for an adjacent network node and a maximum size of a data packet for the interface on the particular network node;
• and
• means for including no more than N adjacent network nodes in any subset of the plurality of subsets.

An apparatus for determining a route in a packet-switched communications network, comprising:

• a network interfaces coupled to a first network for communicating therewith a first data packet;
• one or more processors;
• a computer-readable medium;
• and
• one or more sequences of instructions stored in the computer-readable medium, which, when executed by the one or more processors, causes the one or more processors to carry out the steps of:
• determining a plurality of subsets of adjacent network nodes of a packet-switched communications network, which adjacent network nodes communicate without intervening network nodes with the network interface, wherein each subset of the plurality of subsets includes a plurality of adjacent network nodes;
• sending through the network interface, subset definition data that indicates which adjacent network nodes belong to which subset of the plurality of subsets;
• sending data for fewer than all adjacent network nodes in all subsets of the plurality of subsets by including, in a multicast data packet sent over the network interface with a multicast destination address, subset identifier data that indicates a particular subset of the plurality of subsets;
• determining a transport cost to each adjacent network node of the adjacent network nodes;
• determining a range of transport cost for each subset of the plurality of subsets;
• determining whether a first transport cost of a first adjacent network node is in a first range associated with a first subset of the plurality of subsets, and if the first transport cost is in the first range, then including the first adjacent network node in the first subset;
• wherein, said step of determining the plurality of subsets further comprising:
• determining a maximum number N of adjacent network nodes included in anyone subset based on a size of an identifier for an adjacent network node and a maximum size of a data packet for the interface on the particular network node;
• and
• including no more than N adjacent network nodes in any subset of the plurality of subsets.

An apparatus for determining a route in a packet-switched communications network, comprising:

• a network interfaces coupled to a first network for communicating therewith a first data packet;
• one or more processors;
• a computer-readable medium;
• and
• one or more sequences of instructions stored in the computer-readable medium, which, when executed by the one or more processors, causes the one or more processors to carry out the steps of:
• receiving on the network interface from an adjacent network node that communicates without an intervening network node, subset definition data that indicates which network nodes belong to which subset of a plurality of subsets of network nodes wherein each subset of the plurality of subsets includes a plurality of network nodes;
• determining a particular subset identifier associated with the apparatus based on the subset definition data;
• receiving, in a multicast data packet, subset identifier data that indicates a first subset identifier for a first subset of the plurality of subsets;
• determining whether to process the multicast data packet based on whether the first subset identifier matches the particular subset identifier;
• determining a transport cost to each adjacent network node of the adjacent network nodes;
• determining a range of transport cost for each subset of the plurality of subsets;
• determining whether a first transport cost of a first adjacent network node is in a first range associated with a first subset of the plurality of subsets, and if the first transport cost is in the first range, then including the first adjacent network node in the first subset;
• determining a maximum number N of adjacent network nodes included in anyone subset based on a size of an identifier for an adjacent network node and a maximum size of a data packet for the interface on the particular network node;
• and
• including no more than N adjacent network nodes in any subset of the plurality of subsets.