System and methods for computing flooding topology

Patent metadata

Field	Value
Publication number	US-12192097-B2
Application number	US-202318519747-A
Country	US
Kind code	B2
Filing date	Nov 27, 2023
Priority date	Jul 5, 2019
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

Methods of computing a flooding topology (FT) for a network are presented. The methods include a process for computing a FT that includes all nodes in the network and a process for ensuring that all nodes in the FT have at least two links in the FT. Some of the methods minimize a number of links of the nodes in the FT. Some of the methods also constrain some of the nodes in the FT to a maximum number of links. Some of the methods compute a first FT for nodes whose maximum number of links in the FT equal their number of links in the network, then compute a second FT for remaining nodes in the network, then combines the two FTs to compute a complete FT for the network.

First claim

The invention claimed is:

1. A network device, comprising:
a memory configured to store instructions; and
a processor coupled to the memory and configured to execute the instructions stored in the memory to cause the network device to:
select a node R 0 from a plurality of nodes;
initialize a flooding topology (FT) with the node R 0 ;
initialize a candidate queue (Cq);
implement a first loop, wherein the network device:
removes a first node from the Cq and adding the first node to the FT;
determines whether the FT includes all nodes in the plurality of nodes;
terminates the first loop when the FT includes all the nodes in the plurality of nodes; and
appends to the Cq those nodes that are coupled in the plurality of nodes to the first node and are not in the FT when the FT does not include all the nodes in the plurality of nodes; and
adds a link to any node in the FT having only one link in the FT.

2. The network device of claim 1 , wherein, in the first loop, the network device:
determines whether the Cq is empty when the FT does not include all the nodes in the plurality of nodes; and
when the Cq is empty and the FT does not include all the nodes in the plurality of nodes:
transmits a first message to an administrator of the plurality of nodes;
transmits a second message to a component in the network device, wherein the first and second messages indicate an existence of nodes in the plurality of nodes that are unconnected to other nodes of the plurality of nodes; and
terminates the first loop.

3. The network device of claim 1 , wherein, in adding the link to any node in the FT having only one link in the FT, the network device:
implements a second loop, wherein the network device:
determines whether the FT includes a node Q having only one link in the FT;
terminates the second loop with all the nodes in the FT having more than one link in the FT when the FT does not include the node Q; and
when the FT does include the node Q:
creates a set of all nodes that are coupled in the plurality of nodes to the node Q;
selects a node L in the set, the node L having (i) a lowest number of links in the FT, and (ii) a lowest nodeID when two or more nodes have the same lowest number of links in the FT, where nodeID is an identifier of the node L in a topology of the plurality of nodes;
increments by 1 a degree of the node Q in the FT;
increments by 1 the degree of the node L in the FT; and
adds a link between Q and L to the FT.

4. The network device of claim 1 , wherein the node R 0 has a lowest nodeID in the plurality of nodes.

5. The network device of claim 1 , wherein the Cq is initialized with nodes ordered from lowest nodeID to highest nodeID.

6. The network device claim 1 , wherein nodes appended to the Cq are ordered from lowest nodeID to highest nodeID.

7. A network device, comprising:
a memory configured to store instructions; and
a processor coupled to the memory and configured to execute the instructions stored in the memory to cause the network device to:
set an initial value for a maximum degree (MaxD);
implement a first loop, wherein the network device:
selects a node R 0 from a plurality of nodes;
initializes a flooding topology (FT) with the node R 0 ;
adds nodes from the plurality of nodes to the FT;
determines whether the FT includes all nodes in the plurality of nodes;
increments the value of the MaxD; and
repeats the steps of the first loop until the FT includes all the nodes in the plurality of nodes; and
implements a second loop when the FT includes all the nodes in the plurality of nodes, wherein the network device:
adds a link to any node in the FT having only one link in the FT and coupled in the plurality of nodes to a node having a number of links less than MaxD;
determines whether all the nodes in the FT have more than one link in the FT; and
increments the value of the MaxD: and
repeats the first loop and the second loop until all the nodes in the FT have more than one link in the FT.

8. The network device of claim 7 , wherein, in adding the nodes from the plurality of nodes to the FT, the network device:
initializes a candidate queue (Cq) to include all nodes that are coupled in the plurality of nodes to the node R 0 , the nodes being ordered in the Cq by a nodeID of each node, where nodelD is an identifier of the node in a topology of the plurality of nodes; and
implements a third loop, wherein the network device:
determines whether the Cq includes a node X, the node X being a first node in the Cq having a node Y in a Previous Hops (PHs) of the node X, the node Y having a degree less than MaxD;
terminates the third loop with the FT not including all the nodes in the plurality of nodes when the Cq does not include the node X;
removes the node X from the Cq and adding the node X to the FT;
determines whether the FT includes all the nodes in the plurality of nodes;
modifies the Cq when the FT does not include all the nodes in the plurality of nodes; and
terminates the third loop when the FT includes all the nodes in the plurality of nodes.

9. The network device of claim 8 , wherein the Cq is initialized with nodes ordered from lowest nodeID to highest nodeID.

10. The network device of claim 8 , wherein, in modifying the Cq when the FT does not include all the nodes in the plurality of nodes, the network device:
creates a queue of all nodes that are coupled in the plurality of nodes to the node X and are not in the FT, the queue ordered by the nodeID of the nodes in the queue; and
for each node Z in the queue:
determines whether the node Z is in the Cq;
adds the node X to the PHs of the node Z in the Cq when the node Z is in the Cq; and
appends the node Z to the Cq when the node Z is not in the Cq.

11. The network device of claim 10 , wherein nodes appended to the Cq are ordered from lowest nodeID to highest nodeID.

12. The network device of claim 7 , wherein, in adding the link to any node in the FT having only one link in the FT and coupled in the plurality of nodes to the node having a number of links less than MaxD, the network device:
implements a fourth loop, wherein the network device:
determines whether the FT includes a node Q having only one link in the FT;
terminates the fourth loop with all the nodes in the FT having more than one link in the FT when the FT does not include the node Q;
determines whether the FT includes a node L coupled to Q in the plurality of nodes, the node L having (i) a lowest number of links in the FT, (ii) a lowest nodeID when two or more nodes have the same lowest number of links in the FT, and (iii) the degree less than MaxD, when the FT does include the node Q;
when the FT does include the node L:
increments by 1 the degree of the node Q in the FT;
increments by 1 the degree of the node L in the FT; and
adds the node L to the PHs of the node Q in the FT; and
terminates the fourth loop without all the nodes in the FT having more than one link in the FT when the FT does not include the node L.

13. The network device of claim 7 , wherein the node R 0 has a lowest nodeID in the plurality of nodes.

14. A method for computing a flooding topology (FT) in a network device, comprising:
selecting a node R 0 from a plurality of nodes;
initializing the FT with the node R 0 ;
initializing a candidate queue (Cq);
implementing a first loop of the method, comprising:
removing a first node from the Cq and adding the first node to the FT;
determining whether the FT includes all nodes in the plurality of nodes;
terminating the first loop when the FT includes all the nodes in the plurality

Assignees

• Huawei Tech Co Ltd

Inventors

• Chen Huaimo

Classifications

• H04L45/02 Primary

  Topology update or discovery · CPC title

• H04L47/6275

  based on priority · CPC title

• H04L45/42

  Centralised routing · CPC title

• H04L45/32 Primary

  Flooding (denial of service attacks H04L63/1458) · CPC title

• H04L45/16

  Multipoint routing · CPC title