ZyXEL Communications GS1510-16, GS1510-24 IP Source Guard, 18.1 Overview, 18.2What You Can Do, 18.3What You Need To Know

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IP Source Guard

18.1 Overview

Use the IP source guard screens to filter unauthorized DHCP and ARP packets in your network. IP source guard uses a binding table to distinguish between the authorized and unauthorized DHCP and ARP packets in your network.

18.2What You Can Do

•Use the DHCP Snooping screens (Section 18.4 on page 107) to filter unauthorized DHCP packets on the network and to build the binding table dynamically.

•Use the ARP Inspection screens (Section 18.6 on page 110) to filter unauthorized ARP packets on the network.

•Use the Binding Table screens (Section 18.7 on page 112) to manually enter static bindings and to convert dynamic bindings to static.

18.3What You Need To Know

A binding in the IP source guard binding table contains these key attributes:

•MAC address

•VLAN ID

•IP address

•Port number

When the Switch receives an ARP packet, it looks up the appropriate MAC address, VLAN ID, IP address, and port number in the binding table. If there is a binding, the Switch forwards the packet. If there is not a binding, the Switch discards the packet.

The Switch builds the binding table by snooping DHCP packets (dynamic bindings) and from information provided manually by administrators (static bindings).

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GS1510 Series User’s Guide