Implicit topologies

Implicit topologies are complex VPN network configurations that

  • combine elements from the three main VPN topologies (full mesh, hub-and-spoke, and point-to-point)

  • create more sophisticated network architectures than individual topology types, and

  • provide customized connectivity solutions for specific network requirements.

Types of implicit topologies

  • Partial mesh: A network in which some devices are organized in a full mesh topology, and other devices form either a hub-and-spoke or a point-to-point connection to some of the fully meshed devices. A partial mesh does not provide the level of redundancy of a full mesh topology, but it is less expensive to implement. Partial mesh topologies are used in peripheral networks that connect to a fully meshed backbone.

  • Tiered hub-and-spoke: A network of hub-and-spoke topologies in which a device can behave as a hub in one or more topologies and a spoke in other topologies. Traffic is permitted from spoke groups to their most immediate hub.

  • Joined hub-and-spoke: A combination of two topologies (hub-and-spoke, point-to-point, or full mesh) that connect to form a point-to-point tunnel. For example, a joined hub-and-spoke topology could comprise two hub-and-spoke topologies, with the hubs acting as peer devices in a point-to-point topology.