D-Link DFL-2500 User Guide - Page 86

Proxy ARP, Routing

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9.6. ARP 67 To accomplish the above, the firewall provides responses to ARP requests concerning the IP addresses in published ARP items. The latter purpose is useful if there are several separate IP spans on a single LAN. The computers on each IP span may then use a gateway in their own span when these gateway addresses are published on the firewall interface. Another area of use is publishing multiple addresses on an external interface, enabling the firewall to statically address translate communication to these addresses and send it onwards to internal servers with private IP addresses. The difference between XPublish and Publish is that XPublish "lies" about the sender hardware address in the Ethernet header; this is set to be the same as the published hardware address rather than the actual hardware address of the network adapter. If a published hardware address is the same as the hardware address of the network adapter, it will make no difference if you select Publish or XPublish; the net result will be the same. Note In the ARP section, addresses may only be published one at a time. The Routes section on the other hand, can handle publishing entire networks using 10.8 Proxy ARP. Note For published IP addresses to work correctly it might be necessary to add a new route. (See 10 Routing) If an additional address is added for an interface, the core interface should probably be specified as the interface when configuring the route. D-Link Firewalls User's Guide

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9.6. ARP
67
To accomplish the above, the firewall provides responses to ARP requests
concerning the IP addresses in published ARP items. The latter purpose is
useful if there are several separate IP spans on a single LAN. The
computers on each IP span may then use a gateway in their own span when
these gateway addresses are published on the firewall interface.
Another area of use is publishing multiple addresses on an external
interface, enabling the firewall to statically address translate
communication to these addresses and send it onwards to internal servers
with private IP addresses.
The difference between XPublish and Publish is that XPublish ”lies” about
the sender hardware address in the Ethernet header; this is set to be the
same as the published hardware address rather than the actual hardware
address of the network adapter.
If a published hardware address is the same as the hardware address of the
network adapter, it will make no difference if you select Publish or
XPublish; the net result will be the same.
Note
In the ARP section, addresses may only be published one at a time. The
Routes section on the other hand, can handle publishing entire networks
using
10.8 Proxy ARP
.
Note
For published IP addresses to work correctly it might be necessary to add
a new route. (See
10 Routing
) If an additional address is added for an
interface, the core interface should probably be specified as the interface
when configuring the route.
D-Link Firewalls User’s Guide