LevelOne GEL-1061 User Manual page 281

IP – Checks the ARP body for invalid and unexpected IP addresses. These
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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
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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
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By default, logging is active for ARP Inspection, and cannot be disabled.
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The administrator can configure the log facility rate.
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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.
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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.
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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.
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If the log buffer is full, the oldest entry will be replaced with the newest entry.
Parameters
These parameters are displayed:
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ARP Inspection Status – Enables ARP Inspection globally. (Default: Disabled)
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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
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against the target MAC address in the body of ARP responses.
IP – Checks the ARP body for invalid and unexpected IP addresses. Sender
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IP addresses are checked in all ARP requests and responses, while target IP
addresses are checked only in ARP responses.
Allow Zeros – Allows sender IP address to be 0.0.0.0.
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Src-MAC – Validates the source MAC address in the Ethernet header
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against the sender MAC address in the ARP body. This check is performed
on both ARP requests and responses.
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Chapter 12
| Security Measures
ARP Inspection