Backward-recursive path computation using rsvp-te

A system comprising:

• a plurality of nodes in a network that includes a plurality of sections,
• one or more nodes, of the plurality of nodes, being configured to:
• transmit a message, for computing diverse paths through the network from a first section, of the plurality of sections, to a second section of the plurality of sections, using a Resource Reservation Protocol—Traffic Engineering (RSVP-TE) signaling protocol,
• the message being transmitted from a first node, in the first section, to a second node in the second section;
• generate, by the second node in the second section, at least one data structure that identifies multiple diverse entry points to the second section;
• transmit the at least one data structure toward the first node in the first section;
• complete, by the first node in the first section, the at least one data structure to form at least one completed data structure,
• the at least one completed data structure identifying multiple diverse exit points from the first section and the multiple diverse entry points to the second section;
• cause, using a first data structure of the at least one completed data structure, a primary path from the first section to the second section to be established,
• the primary path including a first exit point, of the multiple diverse exit points from the first section, and a first entry point of the multiple diverse entry points to the second section;
• and
• cause, using a second data structure of the at least one completed data structure, a secondary path from the first section to the second section to be established,
• the secondary path including a second exit point, of the multiple diverse exit points from the first section, and a second entry point of the multiple diverse entry points to the second section.

A system comprising:

• a plurality of nodes in a network that includes a plurality of domains or layers,
• one or more nodes, of the plurality of nodes, being configured to:
• transmit a message, for computing diverse paths through the network from a first domain or layer, of the plurality of domains or layers, to a second domain or layer of the plurality of domains or layers, using a Resource Reservation Protocol—Traffic Engineering (RSVP-TE) signaling protocol,
• the message being transmitted from a first node, in the first domain or layer, to a second node in the second domain or layer;
• generate, by the second node in the second domain or layer, at least one data structure that identifies multiple diverse entry points to the second domain or layer;
• transmit the at least one data structure toward the first node in the first domain or layer;
• complete, by the first node in the first domain or layer, the at least one data structure to form at least one completed data structure,
• the at least one completed data structure identifying multiple diverse exit points from the first domain or layer and the multiple diverse entry points to the second domain or layer;
• use a first data structure, of the at least one completed data structure, to compute a primary path from the first domain or layer to the second domain or layer,
• the primary path including a first exit point, of the multiple diverse exit points from the first domain or layer, and a first entry point of the multiple diverse entry points to the second domain or layer;
• and
• use a second data structure, of the at least one completed data structure, to compute a secondary path from the first domain or layer to the second domain or layer,
• the secondary path including a second exit point, of the multiple diverse exit points from the first domain or layer, and a second entry point of the multiple diverse entry points to the second domain or layer.