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WAN architecture
The WAN architecture, normally used to interconnect offices, is mainly implemented using a hub-spoke or a full/partial mesh topology. While other topologies do exist, in the real world, one of these two is used.
However, we are discussing the logical topology, and this might be implemented by using private links, MPLS, or even an internet connection.
The preceding diagram shows how the physical and the logical connectivity might be created for the connection between the different offices. It is an example of the hub-spoke topology, which means if Branch Office 1 has to talk to Branch Office 2, it will have to go through one of the hub routers.
We will take a look at MPLS and VPNs in a later part of the chapter.
The orchestration of this layer (if any) would be, advertising a new route, and possibly opening a pinhole (allowing access through a firewall for an application) in the perimeter security devices.