Bi-Directional Translation

When you Create an NPTv6 Policy, the Bi-directional option in the Translated Packet tab provides a convenient way for you to have the firewall create a corresponding NAT or NPTv6 translation in the opposite direction of the translation you configured. By default, Bi-directional translation is disabled.
If you enable Bi-directional translation, it is very important to make sure you have security policies in place to control the traffic in both directions. Without such policies, the Bi-directional feature will allow packets to be automatically translated in both directions, which you might not want.

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