Dynamic ARP inspection (DAI) is a security feature that validates ARP packets in a network. It intercepts, logs, and discards ARP packets with invalid IP-to-MAC address bindings. This capability protects the network from certain man-in-the-middle attacks. After enabling DAI, all ports become untrusted ports.

You specify primary and secondary actions that the appliance will take when it detects a possible DLP violation in an outgoing message. Different actions can be assigned for different violation types and severities. Primary actions include: - Deliver - Drop - Quarantine Secondary actions include: - Sending a copy to a policy quarantine if you choose to deliver the message. The copy is a perfect clone of the original, including the Message ID. Quarantining a copy allows you to test the DLP system before deployment in addition to providing another way to monitor DLP violations. When you release the copy from the quarantine, the appliance delivers the copy to the recipient, who will have already received the original message. - Encrypting messages. The appliance only encrypts the message body. It does not encrypt the message headers. - Altering the subject header of messages containing a DLP violation. - Adding disclaimer text to messages. - Sending messages to an alternate destination mailhost. - Sending copies (bcc) of messages to other recipients. (For example, you could copy messages with critical DLP violations to a compliance officer's mailbox for examination.) - Sending a DLP violation notification message to the sender or other contacts, such as a manager or DLP compliance officer. Reference: https://www.cisco.com/c/en/us/td/docs/security/esa/esa12-0/user_guide/ b_ESA_Admin_Guide_12_0/b_ESA_Admin_Guide_chapter_010001.html in an outgoing message. Different actions can be assigned for different violation types and severities.
Primary actions include:
- Deliver
- Drop
- Quarantine
Secondary actions include:
- Sending a copy to a policy quarantine if you choose to deliver the message. The copy is a perfect clone of the original, including the Message ID. Quarantining a copy allows you to test the DLP system before deployment in addition to providing another way to monitor DLP violations. When you release the copy from the quarantine, the appliance delivers the copy to the recipient, who will have already received the original message.
- Encrypting messages. The appliance only encrypts the message body. It does not encrypt the message headers.
- Altering the subject header of messages containing a DLP violation.
- Adding disclaimer text to messages.
- Sending messages to an alternate destination mailhost.
- Sending copies (bcc) of messages to other recipients. (For example, you could copy messages with critical DLP violations to a compliance officer's mailbox for examination.)
- Sending a DLP violation notification message to the sender or other contacts, such as a manager or DLP compliance officer.
Reference:
You specify primary and secondary actions that the appliance will take when it detects a possible DLP violation in an outgoing message. Different actions can be assigned for different violation types and severities. Primary actions include: - Deliver - Drop - Quarantine Secondary actions include: - Sending a copy to a policy quarantine if you choose to deliver the message. The copy is a perfect clone of the original, including the Message ID. Quarantining a copy allows you to test the DLP system before deployment in addition to providing another way to monitor DLP violations. When you release the copy from the quarantine, the appliance delivers the copy to the recipient, who will have already received the original message. - Encrypting messages. The appliance only encrypts the message body. It does not encrypt the message headers. - Altering the subject header of messages containing a DLP violation. - Adding disclaimer text to messages. - Sending messages to an alternate destination mailhost. - Sending copies (bcc) of messages to other recipients. (For example, you could copy messages with critical DLP violations to a compliance officer's mailbox for examination.) - Sending a DLP violation notification message to the sender or other contacts, such as a manager or DLP compliance officer. Reference: https://www.cisco.com/c/en/us/td/docs/security/esa/esa12-0/user_guide/ b_ESA_Admin_Guide_12_0/b_ESA_Admin_Guide_chapter_010001.html