Transforming the WAN edge
The simplicity of the legacy WAN architecture is evident, specifically with routing. Its hub-and-spoke design requires each remote site to route all non-local traffic to the hub, regardless of the final destination. Legacy WAN architectures that consist of aging hardware and software solutions continue to provide network connectivity as well as a consistent level of performance and security, and they continue to satisfy some organizations.
However, if an organization needs to add redundancy or additional bandwidth to a legacy WAN infrastructure, complexity can quickly increase. Leveraging private connectivity in a full-mesh approach, for example, would require either multiple static routes or the introduction of a dynamic routing protocol, such as Border Gateway Protocol (BGP) or equal-cost multi-path (ECMP) routing.
For a diagram of the legacy WAN architecture, see Legacy WAN edge .