Managing grey zones of unreachable nodes in computer networks

摘要

In one embodiment, a node (e.g., a root-node) of a currently known directed acyclic graph (DAG) topology of a computer network can identify a sub-DAG of one or more nodes that are unreachable. The node can further determine a scope of the unreachable nodes of the sub-DAG and tunnel a redirected message to a reachable node of the DAG topology that is adjacent to at least one of the unreachable nodes of the sub-DAG. The redirected message may cause the reachable node to distribute the redirected message to one or more of the unreachable nodes of the sub-DAG based on the scope.

主权项

1. A method, comprising:
identifying, within a currently known directed acyclic graph (DAG) topology of a computer network, a sub-DAG of nodes that are unreachable, wherein the sub-DAG of unreachable nodes is a grey zone, the grey zone an area of the network where there is a lack of proper routing information to properly forward messages even though a feasible underlying path could exit; determining a scope of the unreachable nodes of the sub-DAG; tunneling a redirected message to a reachable node of the DAG topology that is adjacent to at least one of the unreachable nodes of the sub-DAG, the redirected message causing the reachable node to distribute the redirected message to one or more of the unreachable nodes of the sub-DAG based on the scope, wherein the redirected message has a time-to-live (TTL); determining that the redirected message cannot reach a particular unreachable node of the one or more unreachable nodes; increasing the TTL of the redirected message yielding a second redirected message; and tunneling the second redirected message to the reachable node to cause the reach-able node to distribute the redirected message to the particular unreachable node with the increased TTL.