D-Link DFL-260E User Manual page 96

3.3.2. Ethernet Interfaces
The names of the Ethernet interfaces are predefined by the system, and are mapped to the names
of the physical interfaces.
The names of the Ethernet interfaces can be changed to better reflect their usage. For example, if
an interface named dmz is connected to a wireless LAN, it might be convenient to change the
interface name to radio. For maintenance and troubleshooting, it is recommended to tag the
corresponding physical interface with the new name.
• IP Address
Each Ethernet interface is required to have an Interface IP Address, which can be either a static
address or an address provided by DHCP. The interface IP address is used as the primary
address for communicating with the system through the specific Ethernet interface.
NetDefendOS IP4 Address objects are usually used to define the IP addresses of Ethernet
interfaces. Those objects are normally auto-generated by the system. For more information,
please see Section 3.1.5, "Auto-Generated Address Objects".
• Network
In addition to the interface IP address, a Network address is also specified for an Ethernet
interface. The Network address provides information to NetDefendOS about what IP addresses
are directly reachable through the interface. In other words, those residing on the same LAN
segment as the interface itself. In the routing table associated with the interface, NetDefendOS
will automatically create a direct route to the specified network over the actual interface.
• Default Gateway
A Default Gateway address can optionally be specified for an Ethernet interface. This is a
normally the address of a router and very often the router which acts as the gateway to the
Internet.
Normally, only one default all-nets route to the default gateway needs to exist in the routing
table.
• Enable DHCP Client
NetDefendOS includes a DHCP client feature for dynamic assignment of address information by
a connected DHCP server. This feature is often used for receiving external IP address
information from an ISP's DHCP server for public Internet connection.
The information that can be set using DHCP includes the IP address of the interface, the local
network that the interface is attached to, and the default gateway.
Note: Interface enumeration
The startup process will enumerate all available Ethernet interfaces. Each
interface will be given a name of the form lanN, wanN and dmz, where N
represents the number of the interface if the NetDefend Firewall has more than one
of these interfaces. In most of the examples in this guide lan is used for LAN traffic
and wan is used for WAN traffic. If the NetDefend Firewall does not have these
interface names, please substitute the references with the actual names of the
interfaces.
Tip: Specifying multiple IP addresses on an interface
Multiple IP addresses can be specified for an Ethernet interface by using the ARP
Publish feature. (For more information, see Section 3.4, "ARP").
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Chapter 3. Fundamentals