LevelOne GTL-2691 User Manual

Page 372

HAPTER

| Security Measures

ARP Inspection

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with different MAC addresses are classified as invalid and are

dropped.

■

IP – Checks the ARP body for invalid and unexpected IP addresses.

These addresses include 0.0.0.0, 255.255.255.255, and all IP

multicast addresses. Sender IP addresses are checked in all ARP

requests and responses, while target IP addresses are checked only

in ARP responses.

■

Source MAC – Checks the source MAC address in the Ethernet

header against the sender MAC address in the ARP body. This check

is performed on both ARP requests and responses. When enabled,

packets with different MAC addresses are classified as invalid and
are dropped.

ARP Inspection Logging

◆

By default, logging is active for ARP Inspection, and cannot be disabled.

◆

The administrator can configure the log facility rate.

◆

When the switch drops a packet, it places an entry in the log buffer,

then generates a system message on a rate-controlled basis. After the

system message is generated, the entry is cleared from the log buffer.

◆

Each log entry contains flow information, such as the receiving VLAN,

the port number, the source and destination IP addresses, and the

source and destination MAC addresses.

◆

If multiple, identical invalid ARP packets are received consecutively on

the same VLAN, then the logging facility will only generate one entry in

the log buffer and one corresponding system message.

◆

If the log buffer is full, the oldest entry will be replaced with the newest

entry.

ARAMETERS

These parameters are displayed:

◆

ARP Inspection Status – Enables ARP Inspection globally.

(Default: Disabled)

◆

ARP Inspection Validation – Enables extended ARP Inspection

Validation if any of the following options are enabled.

(Default: Disabled)

■

Dst-MAC – Validates the destination MAC address in the Ethernet

header against the target MAC address in the body of ARP

responses.

■

IP – Checks the ARP body for invalid and unexpected IP addresses.

Sender IP addresses are checked in all ARP requests and responses,

while target IP addresses are checked only in ARP responses.