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HAPTER
7
| Security Measures
ARP Inspection
– 224 –
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EB
I
NTERFACE
To show information on TCAM utilization:
1.
Click Security, ACL, TCAM Utilization.
Figure 94: Showing TCAM Utilization
ARP I
NSPECTION
ARP Inspection is a security feature that validates the MAC Address
bindings for Address Resolution Protocol packets. It provides protection
against ARP traffic with invalid MAC-to-IP address bindings, which forms
the basis for certain “man-in-the-middle” attacks. This is accomplished by
intercepting all ARP requests and responses and verifying each of these
packets before the local ARP cache is updated or the packet is forwarded to
the appropriate destination. Invalid ARP packets are dropped.
ARP Inspection determines the validity of an ARP packet based on valid
IP-to-MAC address bindings stored in a trusted database – the DHCP
snooping binding database (see
). This database is built
by DHCP snooping if it is enabled on globally on the switch and on the
required VLANs. ARP Inspection can also validate ARP packets against
user-configured ARP access control lists (ACLs) for hosts with statically
configured addresses (see
C
OMMAND
U
SAGE
Enabling & Disabling ARP Inspection
ARP Inspection is controlled on a global and VLAN basis.
By default, ARP Inspection is disabled both globally and on all VLANs.
If ARP Inspection is globally enabled, then it becomes active only on
the VLANs where it has been enabled.
When ARP Inspection is enabled globally, all ARP request and reply
packets on inspection-enabled VLANs are redirected to the CPU and
their switching behavior handled by the ARP Inspection engine.
If ARP Inspection is disabled globally, then it becomes inactive for
all VLANs, including those where inspection is enabled.
Summary of Contents for DG-FS4528P
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Page 148: ...CHAPTER 5 Simple Network Management Protocol Configuring SNMPv3 Groups 148 ...
Page 389: ...CHAPTER 17 VoIP Traffic Configuration Configuring Telephony OUI 389 ...
Page 515: ...CHAPTER 22 System Management Commands UPnP 515 TTL 20 Console ...
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Page 973: ...DG FS4528P ...