H3C Technologies H3C S6300 Series Switches - Manual (Page 337)

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Configuring ARP attack protection
ARP attacks and viruses are threatening LAN security. This chapter describes multiple features used to
detect and prevent ARP attacks.
Although ARP is easy to implement, it provides no security mechanism and is vulnerable to network
attacks. An attacker can exploit ARP vulnerabilities to attack network devices in the following ways:
• Acts as a trusted user or gateway to send ARP packets so the receiving devices obtain incorrect ARP
entries.
• Sends a large number of unresolvable IP packets to have the receiving device busy with resolving IP
addresses until its CPU is overloaded. Unresolvable IP packets refer to IP packets for which ARP
cannot find corresponding MAC addresses.
• Sends a large number of ARP packets to overload the CPU of the receiving device.
For more information about ARP attack features and types, see ARP Attack Protection Technology White
Paper.
ARP attack protection configuration task list
Tasks at a glance
Flood prevention:
• Configuring unresolvable IP attack protection (configured on gateways)
{
Configuring ARP source suppression
{
Configuring ARP blackhole routing
• Configuring ARP packet rate limit (configured on access devices)
• Configuring source MAC-based ARP attack detection (configured on gateways)
User and gateway spoofing prevention:
• Configuring ARP packet source MAC consistency check (configured on gateways)
• Configuring ARP active acknowledgement (configured on gateways)
• Configuring authorized ARP (configured on gateways)
• Configuring ARP detection (configured on access devices)
• Configuring ARP scanning and fixed ARP (configured on gateways)
• Configuring ARP gateway protection (configured on access devices)
• Configuring ARP filtering (configured on access devices)
Configuring unresolvable IP attack protection
If a device receives a large number of unresolvable IP packets from a host, the following situations can
occur.
• The device sends a large number of ARP requests, overloading the target subnets.
• The device keeps trying to resolve the destination IP addresses, overloading its CPU.
To protect the device from such unresolvable IP attacks, you can configure the following features: