Cabletron Systems CSX1200, CSX1000 manual Example 1 LAN, WAN and WAN Direct Host Interfaces

CONFIGURING BASIC IP ROUTING

IP Network Interfaces

	File
Host	Server	Subnet 128.1.1.0

128.1.1.8128.1.1.3

(128.1.1.2 uses WAN Direct Host Interface) Host

128.1.1.1

128.1.1.2

Interfaces:

LAN Interface 128.1.1.1

WAN Direct Host Interface

192.2.2.1

Subnet 192.2.2.0

Needed for

WAN Interface

192.2.2.3

Router

198.1.2.3

Subnet 198.1.2.0

(Uses WAN Interface)

WAN Interface 192.2.2.1 both WAN Interfaces use one PRI line

ISDN

Example 1: LAN, WAN and WAN Direct Host Interfaces

In example 1, we show three different types of network interfaces and the IP subnets that are used. It should be noted that even though the CyberSWITCH only has one physical connection to the WAN, it has more than one logical connection. Also, each one of these logical interfaces can be in different subnetworks.

•The LAN interface is the simplest. It specifies the IP address (128.1.1.1) which connects the sys- tem to the Ethernet LAN. In our example, only one LAN interface is configured.

•The Direct Host interface doesn’t have an IP address. Devices that use the Direct Host interface must have an IP address that is on the same subnet as one of the configured LAN interfaces. Since only one LAN interface is configured, that IP address must correspond to the one config- ured LAN IP address. (See Secondary IP Addressing for multiple LAN IP addresses).

•The WAN interface in this example is used to connect two IP subnets (128.1.1.0 and 198.1.2.0). A separate subnet (192.2.2.0) is required to connect the subnets. If the remote router supports unnumbered interfaces (such as Example 2), then the connecting subnet would not be required.

Workgroup Remote Access Switch 115