Network > ARP
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SonicOS Enhanced 4.0 Administrator Guide
ARP (Address Resolution Protocol) maps layer 3 (IP addresses) to layer 2 (physical or MAC
addresses) to enable communications between hosts residing on the same subnet. ARP is a
broadcast protocol that can create excessive amounts of network traffic on your network. To
minimize the broadcast traffic, an ARP cache is maintained to store and reuse previously
learned ARP information.
Static ARP Entries
The Static ARP feature allows for static mappings to be created between layer 2 MAC
addresses and layer 3 IP addresses, but also provides the following capabilities:
• Publish Entry - Enabling the Publish Entry option in the Add Static ARP window causes
the SonicWALL device to respond to ARP queries for the specified IP address with the
specified MAC address. This can be used, for example, to have the SonicWALL device
reply for a secondary IP address on a particular interface by adding the MAC address of
the SonicWALL. See the Secondary Subnet section that follows.
• Bind MAC Address - Enabling the Bind MAC Address option in the Add Static ARP
window binds the MAC address specified to the designated IP address and interface. This
can be used to ensure that a particular workstation (as recognized by the network card's
unique MAC address) can only the used on a specified interface on the SonicWALL. Once
the MAC address is bound to an interface, the SonicWALL will not respond to that MAC