Hub-Spoke vs. Spoke-Spoke

Hub-Spoke

• Each remote site is connected with a point-to-point GRE tunnel to a pre-defined central node (Hub).

• Hub accepts new tunnel connections from Spokes (branch nodes).

• Data communication (over the overlay network) between Spokes is relayed via the Hub.

• Multiple Hubs may exist to provide redundancy.

Spoke-Spoke

• Individual branch office nodes can dynamically initiate tunnel connections between each other, bypassing the Hub node.

• Data communication (over the overlay network) can be direct between Spokes.

• Dynamic IGP routing protocols may operate between Spoke and Hubs, but not between Spokes.

• No interoperability with non-Cisco IOS routers.