Control Policy Example 1: Hierarchical Topology

Control Policy Example 1: Hierarchical Topology

Building a hierarchical SD-WAN overlay:

• Limits Bidirectional Forwarding Detection (BFD) sessions to intraregion and between hubs.

• Adapts routing to support the desired topology.

By default, Cisco SD-WAN brings up a full-mesh network. Typically, traffic must be aggregated in a region when a network grows, following the available bandwidth. In this case, hub sites that connect to other hub sites are introduced, which connect to other hub sites.

Each regional WAN Edge device sends all traffic destined for any other region to its local hub. Each hub sends traffic for other regions to that region's respective hub router.