BGP aggregation in Clos networks

A system comprising:

• one or more processors;
• and
• at least one computer-readable storage medium having stored therein instructions which, when executed by the one or more processors, cause the one or more processors to:
• determine an unreachable prefix component of a first aggregate route received by a first network node from one or more first next hop nodes, wherein the first network node is a northbound node to the one or more first next hop nodes;
• and
• when the prefix component is identified as a priority prefix,
• announce, to one or more neighboring nodes, the first aggregate route, the unreachable prefix component, and the one or more first next hop nodes, wherein the one or more neighboring nodes are on a same tier as the first network node in a Clos topology;
• identify, by the one or more neighboring nodes, a second aggregate route, the second aggregate route being a shortest aggregate route containing the first aggregate route, the one or more neighboring nodes searching routing table information to yield the second aggregate route after the first aggregate route, the prefix component, and the one or more first next hop nodes are announced;
• and
• generate, from the second aggregate route, one or more Chad routes to the unreachable prefix component, the one or more Chad routes associated with one or more next hop nodes that are different from the one or more next first next hop nodes.

One or more non-transitory computer-readable media comprising computer-readable instructions which, when executed by one or more processors of a network node, cause the network node to:

• determine an unreachable prefix component of a first aggregate route received by a first network node from one or more first next hop nodes, wherein the first network node is a northbound node to the one or more first next hop nodes;
• and
• when the prefix component is identified as a priority prefix, announce, to one or more neighboring nodes, the first aggregate route, the unreachable prefix component, and the one or more first next hop nodes, wherein the one or more neighboring nodes are on a same tier as the first network node in a Clos topology;
• identify, by the one or more neighboring nodes, a second aggregate route, the second aggregate route being a shortest aggregate route that contains the first aggregate route, the one or more neighboring nodes searching routing table information to yield the second aggregate route after the first aggregate route, the prefix component, and the one or more first next hop nodes are announced;
• and
• generate, from the second aggregate route, one or more Chad routes to the unreachable prefix component, the one or more Chad routes associated with one or more next hop nodes that are different from the one or more next first next hop nodes.