A large-sized network has a large number of branch offices. The deployment of Non-Shortcut Scenario of DSVPN requires the Spokes to have a large routing table and high forwarding performance. Shortcut Scenario of DSVPN can be deployed without upgrading the Spokes. This deployment reduces the routing entries on the Spokes, lowering the requirements on the Spokes' routing table size and forwarding performance.
As shown in Figure 1, all the Spokes only have routes to the Hub. When two Spokes need to communicate with each other, the first packet is sent to the Hub. After that, a tunnel is established between the Spokes, and the Spokes can directly exchange data traffic.