Depending on your business needs, a traditional WAN may hinder growth and agility requirements. Forward-thinking IT leaders should weigh these disadvantages against their strategic plans. 

Failover (switching to a standby server or system when your primary application goes down) is completely dependent upon the state of the link (up/down). This means you must depend on routing protocol re-convergence. This can cause multiple seconds worth of outage, resulting in dropped or lost video or phone calls.

Configuration is distributed, meaning that configuration is housed locally on each individual router, but is typically templated.

New policies must be managed on a per-device basis and require your administrator to touch each individual device as policies change.

Significant time is needed for new site turn-up. This includes time for circuit delivery, equipment provisioning, and change management. New sites can take months to turn up due to the complexities of change management and project coordination.

What's all the buzz around SD-WAN?
SD-WAN is a shift in the way a Wide Area Network is deployed and managed. As its name implies, SD-WAN is a software-driven technology with application awareness that is managed from a centralized point in the network.

Leanr more information about the MPLS vs internet.

SD-WAN solutions are deployed as an overlay technology to an existing topology, which allows for ease of integration and adoption over time. 
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