Digisol DG-GS4826S, Management Manual

Page: 336 / 1344

C
HAPTER
14 | Security Measures
ARP Inspection
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with different MAC addresses are classified as invalid and are
dropped.
n
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.
n
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
u
By default, logging is active for ARP Inspection, and cannot be disabled.
u
The administrator can configure the log facility rate.
u
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.
u
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.
u
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.
u
If the log buffer is full, the oldest entry will be replaced with the newest
entry.
P
ARAMETERS
These parameters are displayed in the web interface:
u
ARP Inspection Status – Enables ARP Inspection globally.
(Default: Disabled)
u
ARP Inspection Validation – Enables extended ARP Inspection
Validation if any of the following options are enabled.
(Default: Disabled)
n
Dst-MAC – Validates the destination MAC address in the Ethernet
header against the target MAC address in the body of ARP
responses.
n
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.