Compatible Systems 5.4 - Manual (Page 33)

Chapter 2 - IP Routing & Bridging 27
v Note: The IP Bridging radio button will be grayed out unless bridging has
been turned on globally for the device using the Main Bridging Configuration
Dialog Box (under Global/Bridging) and locally on this interface using the
Bridging: WAN Dialog Box (under WAN/Bridging).
• If set to IP Off, then any IP packets received on this interface are
discarded.
> Numbered Interface
This check box determines whether the Wide Area Network connected to this
interface will have an IP network number associated with it.
Many WAN connections are simple point-to-point links. These links do not
generally require a network number because there are only two devices on the
link. All traffic sent from one end is, by definition, destined for the other end.
You generally do not need a numbered WAN interface if you are using the
PPP transport protocol.
In contrast, Frame Relay networks may have a number of participating
routers connected through a single physical interface. Because of this, use of
the Frame Relay transport protocol requires a numbered WAN interface.
• If checked, then you must set an IP Address, Subnet Mask, and Broad-
cast Address (as described below) for this WAN interface. The default is
unchecked.
v Note: If you are connecting the router to an Internet Service Provider
using PPP, you may be required to use a numbered interface. Check with
their tech support staff.
IP Address
Every network interface on an IP internetwork must have a unique IP address
that identifies that interface to other devices on the internetwork. Part of this
address identifies the network segment the router interface is connected to,
and the remainder uniquely identifies the router interface itself.
This address should be entered as four decimal numbers separated by periods
-- for example, 198.238.9.5
v Note: The single most common problem encountered in IP networking is
the use of a duplicate IP address. You must carefully track the network
numbers you have assigned to various devices in order to avoid hard-to-diag-
nose problems.
Network IP Subnet Mask
Most IP networks use “subnetting” in order to subdivide a large network into
smaller logical sub-networks. The subnet mask value is used to tell the router