Seamless support and node-by-node migration for multiple distributed flood reduction algorithms in the same network

A first network device, comprising:

• one or more memories;
• and
• one or more processors to:
• receive a modified link state protocol (LSP) data unit that is also provided to a plurality of other network devices in a first tier of a network that includes the first network device;
• determine, based on the modified LSP data unit, whether an origin of the modified LSP data unit is executing an algorithm and a version of the algorithm that is the same as an algorithm and a version being executed by the first network device;
• calculate a shortest-path spanning tree (SPT);
• set metrics to one for links associated with the first network device and the plurality of other network devices based on determining that the origin of the modified LSP data unit is executing an algorithm and a version of the algorithm that is not the same as an algorithm and a version being executed by the first network device;
• truncate the SPT to two hops to determine a flooding group that includes the first network device and the plurality of other network devices;
• select a member of the flooding group to flood the modified LSP data unit;
• cause the member to provide the modified LSP data unit to a second network device in a second tier of the network;
• and
• cause other members of the flooding group to not provide the modified LSP data unit to the second network device.

A non-transitory computer-readable medium storing a set of instructions, the set of instructions comprising:

• one or more instructions that, when executed by one or more processors of a first network device in a first tier of a network, cause the first network device to:
• utilize an intermediate-system-to-intermediate-system cryptographic authentication to receive a modified link state protocol (LSP) data unit that is also provided to a plurality of other network devices in the first tier;
• determine, based on the modified LSP data unit, whether an origin of the modified LSP data unit is executing an algorithm and a version of the algorithm that is the same as an algorithm and a version being executed by the first network device;
• calculate a shortest-path spanning tree (SPT);
• set metrics to one for links associated with the first network device and the plurality of other network devices based on determining that the origin of the modified LSP data unit is executing an algorithm and a version of the algorithm that is not the same as an algorithm and a version being executed by the first network device;
• truncate the SPT to two hops to determine a flooding group that includes the first network device and the plurality of other network devices;
• select a member of the flooding group to flood the modified LSP data unit;
• and
• cause the member to provide the modified LSP data unit to a second network device in a second tier of the network.