System and method for traffic engineering information summary of a zone in network communications

An apparatus comprising:

• a hardware processor configured to:
• compute traffic engineering (TE) link state information for every TE link internal to a topology transparent zone (TTZ) from a root node to one or more non-root edge nodes, wherein the TE link state information for every TE link comprises a maximum bandwidth of a TE link;
• compute TE link state information for every TE link internal to the TTZ from one or more internal nodes of the TTZ to the root node or to the one or more non-root edge nodes, wherein the TE link state information for every TE link comprises a maximum bandwidth of a TE link, wherein computing the TE link state information comprises:
• establishing a first list of one or more node-and-bandwidth pairs, wherein a node in each node-and-bandwidth pair is associated with one of the one or more non-root edge node or one of the one or more nodes internal to the TTZ, and wherein bandwidth in each node-and-bandwidth pair is a maximum utilizable bandwidth on a TE link from the root node to the node of the node-and-bandwidth pair;
• establishing a second list;
• selecting a node-and-bandwidth pair of the one or more node-and bandwidth pairs from the first list based on bandwidth;
• adding the selected node-and-bandwidth pair to the second list;
• removing the node-and-bandwidth pair from the first list;
• expanding the first list based on the selected node-and-bandwidth pair;
• and
• repeat the selecting, the adding, the removing and the expanding node-and-bandwidth pairs until either the first list contains no node-and-bandwidth pairs, or every edge node of the TTZ is present in a node-and-bandwidth pair on the second list;
• summarize, in a table, the computed TE link state information for every TE link internal to the TTZ from the root node and the computed TE link state information for every TE link internal to the TTZ from the one or more internal nodes;
• distribute at least a portion of the computed TE link state information in the table to at least one neighboring node external to the TTZ and connected to the root node via an external link;
• and
• establish an end-to-end (E2E) TE label switching path (LSP) comprising a first node external to the TTZ, the root node, a particular edge node of the TTZ, and a second node external to the TTZ, wherein the first node uses at least a portion of the distributed TE link state information to get, set up, and transfer data over a portion of a path to the root node, wherein the root node uses TTZ-internal links to get, set up, and transfer data over the portion of the path to the particular edge node, and wherein the edge node uses TTZ-external links to get, set up, and transfer data over the portion of the path to the second node.

A computer program product comprising computer executable instructions stored on a non-transitory medium that when executed by a hardware processor cause the processor to:

• compute traffic engineering (TE) link state information for every TE link internal to a topology transparent zone (TTZ) from a root node to one or more non-root edge nodes, wherein the TE link state information for every TE link comprises a maximum bandwidth of a TE link, wherein computing the TE link state information comprises:
• establishing a first list of one or more node-and-bandwidth pairs, wherein a node in each node-and-bandwidth pair is associated with one of the one or more non-root edge nodes or one or more nodes internal to the TTZ, and wherein bandwidth in each node-and-bandwidth pair is a maximum utilizable bandwidth on a TE link from the root node to the node of the node-and-bandwidth pair;
• establishing a second list;
• selecting a node-and-bandwidth pair of the one or more node-and bandwidth pairs from the first list based on bandwidth;
• adding the selected node-and-bandwidth pair to the second list;
• removing the node-and-bandwidth pair from the first list;
• expanding the first list based on the selected node-and-bandwidth pair;
• and
• repeat the selecting, the adding, the removing, and the expanding node-and-bandwidth pairs until either the first list contains no node-and-bandwidth pairs, or every edge node of the TTZ is present in a node-and-bandwidth pair on the second list;
• summarize the computed TE link state information in a table;
• distribute at least a portion of the TE link state information in the table to at least one neighboring node external to the TTZ and connected to the root node via an external link;
• and
• establish an end-to-end (E2E) TE label switching path (LSP) comprising a first node external to the TTZ, the root node, a particular edge node of the TTZ, and a second node external to the TTZ, wherein the first node uses at least a portion of the distributed TE link state information to get, set up, and transfer data over a portion of the path to the root node, wherein the root node uses TTZ-internal links to get, set up, and transfer data over the portion of the path to the edge node, and wherein the particular edge node uses TTZ-external links to get, set up, and transfer data over the portion of the path to the second node.