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4) What is EdgeView Security Mechanism
5) Why not just use SSH
SSH works fine if the user laptop and the edge device on the same network, either they are all on Internet or in private VPN network. If the edge device is behind NAT, firewall, LTE or proxy server, and the user's laptop is not, then SSH will not work. Also in the case of the user and device belong to the same network, if multiple users want to access the device, they all need to share the private SSH key. Sometimes that is not desirable.
6) Why not just use SD-WAN
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