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Configuring attack detection and prevention
Overview
Attack detection and prevention enables a device to detect attacks by inspecting arriving packets, and
to take prevention actions, such as packet dropping, to protect a private network.
The device supports only TCP fragment attack prevention.
Configuring TCP fragment attack prevention
The TCP fragment attack prevention feature enables the device to drop attack TCP fragments to prevent
TCP fragment attacks that traditional packet filter cannot detect. As defined in RFC 1858, attack TCP
fragments refer to the following TCP fragments:
•
First fragments in which the TCP header is smaller than 20 bytes.
•
Non-first fragments with a fragment offset of 8 bytes (FO=1).
To configure TCP fragment attack prevention:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enable TCP fragment attack
prevention.
attack-defense tcp fragment
enable
By default, TCP fragment attack
prevention is enabled.