Network : Network > Interfaces : Decrypt Mirror Interface

Decrypt Mirror Interface
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To use the Decryption Port Mirror feature, you must select the Decrypt Mirror interface type. This feature enables creating a copy of decrypted traffic from a firewall and sending it to a traffic collection tool that can receive raw packet captures—such as NetWitness or Solera—for archiving and analysis. Organizations that require comprehensive data capture for forensic and historical purposes or data leak prevention (DLP) functionality require this feature. To enable the feature, you must acquire and install the free license.
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To configure a decrypt mirror interface, click the name of an Interface (ethernet1/1, for example) that is not configured and specify the following information.
Select Decrypt Mirror.
Select the interface speed in Mbps (10, 100, or 1000), or select auto to have the firewall automatically determine the speed.
Select whether the interface transmission mode is full-duplex (full), half-duplex (half), or negotiated automatically (auto).
Select whether the interface status is enabled (up), disabled (down), or determined automatically (auto).
Network > Interfaces