Compatible Systems 5.4 manual Numbered Interface, IP Address

Chapter 2 - IP Routing & Bridging 27

ϖNote: 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.

ϖNote: 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

ϖNote: 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