The use of SD-WAN can also introduce points of failure to the branch office network. In traditional branch Networking, often branch routers go for years without needing any intervention like configuration changes or firmware updates. But SD-WAN routers are more sophisticated and run on a larger software stack. Firmware updates are common which means that there are many more opportunities for things to go wrong.

Updates can leave organizations vulnerable to potential downtime; and visibility blind spots can decrease the effectiveness of deployments, creating security challenges. In an SD-WAN network, for example, it is difficult for engineers using traditional network management tools to find unauthorized IoT devices. Added to this, the fact that SD-WAN doesn't provide the visibility that organizations need to ensure these IT applications work as required, makes it equally difficult to monitor or troubleshoot sites and underlay networks. And while Cloud-Based Provisioning makes Provisioning and configuration of an SD-WAN router easier, ultimately it is still in-band management, with all access to your network dependent on the same router.

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