Abstract: The disclosed method may include (1) identifying, at a first node, a preconfigured level of the first node, (2) receiving, at the first node from a second node, a neighbor advertisement that includes a preconfigured level of the second node, (3) determining that a difference between the preconfigured level of the first node and the preconfigured level of the second node is equal to one, (4) recording, at the first node based on the difference being equal to one, an adjacency relationship between the first node and the second node, (5) transmitting a first type of routing-protocol packet from the first node to the second node based on the adjacency relationship, and (6) refraining from transmitting a second type of routing-protocol packet from the first node to the second node based on the adjacency relationship. Various other apparatuses, systems, and methods are also disclosed.

Abstract: The disclosed method may include (1) identifying, at a first node, a preconfigured level of the first node, (2) receiving, at the first node from a second node, a neighbor advertisement that includes a preconfigured level of the second node, (3) determining that a difference between the preconfigured level of the first node and the preconfigured level of the second node is equal to one, (4) recording, at the first node based on the difference being equal to one, an adjacency relationship between the first node and the second node, (5) transmitting a first type of routing-protocol packet from the first node to the second node based on the adjacency relationship, and (6) refraining from transmitting a second type of routing-protocol packet from the first node to the second node based on the adjacency relationship. Various other apparatuses, systems, and methods are also disclosed.

Abstract: This invention relates to a method to effect hop-by-hop routing in a network segment where different nodes have different views of the network topology. In particular, the methods of this invention are applicable when each node in a network or network segment may be aware of only a subset of the communication links in the network, without perceiving other communication links. Based on each node's individual view of the network, the method introduces the concept of a visibility set that includes all visible communication links. More specifically, an efficient algorithm is disclosed for searching for a family of one-to-all optimal feasible paths in communication network where different nodes may have different views of the network topology.

Abstract: The number of possible circuits that can be linked to each node operating in accordance with the IS-IS standard is expanded from the 256 limit set by the IS-IS standard to a larger arbitrary number. Each node is initially assigned and can use on each circuit a pseudonode ID containing any arbitrary, non-zero circuit ID. This status continues until it is determined that the said node is to become DIS on this LAN; if that happens, the arbitrary circuit ID is abandoned, and the system itself is allowed (using the IS-IS standard process) to reassign a pseudonode ID containing a circuit ID that is indeed unique on the LAN and therefore unused. If the said node has not been determined as DIS on the LAN, it continues to use the arbitrarily assigned circuit ID.