Interlogix NS3500-28T-4S User Manual - Manual (Page 252)

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4.9.7 DHCP Snooping
4.9.7.1 DHCP Snooping Overview
The addresses assigned to DHCP clients on unsecure ports can be carefully controlled using the dynamic bindings
registered with DHCP Snooping. DHCP snooping allows a switch to protect a network from rogue DHCP servers or
other devices which send port-related information to a DHCP server. This information can be useful in tracking an IP
address back to a physical port.
Command Usage
 Network traffic may be disrupted when malicious DHCP messages are received from an outside source.
DHCP
snooping is used to filter DHCP messages received on a non-secure interface from outside the network or
firewall . When DHCP snooping is enabled globally and enabled on a VLAN interface, DHCP messages received
on an untrusted interface from a device not listed in the DHCP snooping table will be dropped .
 Table entries are only learned for trusted interfaces. An entry is added or removed dynamically to the DHCP
snooping table when a client receives or releases an IP address from a DHCP server. Each entry includes a MAC
address, IP address, lease time, VLAN identifier, and port identifier.