Installation guide

General Security Measures
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• If IP source guard is enabled, an inbound packet’s IP address (sip option) or both
its IP address and corresponding MAC address (sip-mac option) will be checked
against the binding table. If no matching entry is found, the packet will be dropped.
• Filtering rules are implemented as follows:
- If the DHCP snooping is disabled (see page 3-117), IP source guard will check
the VLAN ID, source IP address, port number, and source MAC address (for the
sip-mac option). If a matching entry is found in the binding table and the entry
type is static IP source guard binding, the packet will be forwarded.
- If the DHCP snooping is enabled, IP source guard will check the VLAN ID,
source IP address, port number, and source MAC address (for the sip-mac
option). If a matching entry is found in the binding table and the entry type is
static IP source guard binding, or dynamic DHCP snooping binding, the packet
will be forwarded.
- If IP source guard if enabled on an interface for which IP source bindings have
not yet been configured (neither by static configuration in the IP source guard
binding table nor dynamically learned from DHCP snooping), the switch will drop
all IP traffic on that port, except for DHCP packets.
Command Attributes
• Filter Type – Configures the switch to filter inbound traffic based source IP
address, or source IP address and corresponding MAC address. (Default: None)
• None – Disables IP source guard filtering on the port.
• SIP – Enables traffic filtering based on IP addresses stored in the binding table.
• SIP-MAC – Enables traffic filtering based on IP addresses and corresponding
MAC addresses stored in the binding table.
Web – Click IP Source Guard, Port Configuration. Set the required filtering type for
each port and click Apply.
Figure 3-74 IP Source Guard Port Configuration