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How to make the transition to a software defined WAN
SD-WAN solutions must provide operational capabilities such as network-aware orchestration
This vendor-written primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter’s approach.
Software Defined WAN makes it possible to create a transparent, logical enterprise IP network across a mix of service provider technologies and add advanced features such as application-based traffic routing or custom security provisions to meet strict compliance requirements.
However, operating such a network on top of various underlying network architectures—at scale—remains difficult, and SD-WAN overlay networks cannot, per se, address poor-performing WAN connections. The key is being able to manage the underlying network architecture, which is handled differently by the various vendors in the business, each of which has its particular focus and strengths. In general, they can be classified as follows:
* Controller-based solutions—mostly vendor specific—that can auto-discover and configure standard network architectures on vendor’s network devices. These solutions work effectively when environments are highly standardized. Their main focus is to reduce the complexity of managing a large number of devices consistently. They provide a single point of administration, but multiple controllers may be needed depending on network architecture and policy requirements.
* Appliance-based overlay solutions that create a virtual IP network between the vendor’s own appliances across any network. Overlay solutions are an attractive choice for many because they can be deployed quickly. They typically use vendor-proprietary appliances and software. This approach results in solutions with features not available with open networking standards, but can lack customizability, and are dependent on the performance of the underlying infrastructure complicating root cause analysis and troubleshooting. End-users must also turn to an additional hardware vendor to manage for support and lifecycle management.
* Advanced automation and change control solutions that leverage