These are shown in the illustration below of an Ethernet frame containing an ARP response:
Figure 3.2. An ARP Publish Ethernet Frame
The Publish option uses the real MAC address of the sending interface for the address (1) in the
Ethernet frame.
In rare cases, some network equipment will require that both MAC addresses in the response (1 and
2 above) are the same. In this case XPublish is used since it changes both MAC addresses in the
response to be the published MAC address. In other words, XPublish "lies" about the source address
of the ARP response.
If a published MAC address is the same as the MAC address of the physical interface, it will make
no difference if Publish or XPublish is selected, the result will be the same.
Publishing Entire Networks
When using ARP entries, IP addresses can only be published one at a time. However, the
administrator can use the alternative Proxy ARP feature in NetDefendOS to handle publishing of
entire networks (see Section 4.2.6, “Proxy ARP”).
3.5.4. Using ARP Advanced Settings
This section presents some of the advanced settings related to ARP. In most cases, these settings
need not to be changed, but in some deployments, modifications might be needed. A summary of all
ARP advanced settings can be found in the next section.
Multicast and Broadcast
ARP requests and ARP replies containing multicast or broadcast addresses are usually never correct,
with the exception of certain load balancing and redundancy devices, which make use of hardware
layer multicast addresses.
The default behavior of NetDefendOS is to drop and log such ARP requests and ARP replies. This
can, however, be changed by modifying the advanced settings ARP Multicast and ARP Broadcast.
3.5.4. Using ARP Advanced Settings Chapter 3. Fundamentals
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