Routing configuration is required only if your LAN has existing Routers or Gateways. Otherwise, this Chapter can be ignored.
While the ISDN Internet Router includes both RIP 1 (Routing Information Protocol 1) and a standard static routing table, these feature can be completely ignored if you do not have a router in your LAN.
Also, if the ISDN Internet Router is only acting as an Internet Gateway for the local LAN segment, you can ignore the "Routing" screen even if your LAN has other Routers.
Generally, you should use either RIP (Routing Information Protocol) OR the Static Routing Table, although it is possible to use both methods simultaneously.
RIP (Routing Information Protocol) is used by Routers to exchange routing information, and build routing tables in each Router dynamically.
By default, RIP is disabled. Use the following as a guide to determine whether you should enable RIP.
If RIP is not used, an entry in the routing table is required for each LAN segment on your Network, other than the segment to which this device is attached.
The other Routers must also be configured. It is essential that all IP packets for devices not on the local LAN be passed to the ISDN Internet Router, so that they can be forwarded to the Internet. To achieve this, the Routers must be configured to use the ISDN Internet Router as the Default Route or Default Gateway.
The local router is the Router installed on the same LAN segment as the ISDN Internet Router. This router requires that the Default Route is the ISDN Internet Router itself. Typically, routers have a special entry for the Default Route. It should be configured as follows.
Destination IP Address
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Normally 0.0.0.0, but check your router documentation.
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Network Mask
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Normally 0.0.0.0, but check your router documentation.
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Gateway IP Address
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The IP Address of the ISDN Internet Router.
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Metric
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1
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Other routers must use the ISDN Internet Router's Local Router as the Default Route. The entries will be the same as the ISDN Internet Router's local router, with the exception of the Gateway IP Address.
For the LAN shown above, with 2 routers and 3 LAN segments, the required entries would be as follows.
The ISDN Internet Router requires 2 entries as follows.
Entry 1 (Segment 1) |
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Destination IP Address
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192.168.1.0
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Network Mask
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255.255.255.0 (Standard Class C)
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Gateway IP Address
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192.168.0.100 (ISDN Internet Router's local Router)
|
Interface
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LAN
|
Metric
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1
|
Entry 2 (Segment 2) |
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Destination IP Address
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192.168.2.0
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Network Mask
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255.255.255.0 (Standard Class C)
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Gateway IP Address
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192.168.0.100
|
LAN
|
|
Metric
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2
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Destination IP Address
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0.0.0.0
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Network Mask
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0.0.0.0
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Gateway IP Address
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192.168.0.1 (ISDN Internet Router's IP Address)
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Destination IP Address
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0.0.0.0
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Network Mask
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0.0.0.0
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Gateway IP Address
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192.168.1.80 (ISDN Internet Router's local router)
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On the LAN tab, static routing table entries will appear as in the example screen below.
An entry in the routing table is required for each LAN segment on your Network, other than the segment to which this device is attached. The data for each entry is as follows.
RIP |
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Enable RIP
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Check this to enable the RIP (Routing Information Protocol) feature of the
ISDN Internet Router.
The ISDN Internet Router supports RIP 1 only.
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Static Routing Table |
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Select Entry
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This drop-down list shows all entries in the Routing Table.
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Destination
IP Address |
The network address of the remote LAN segment.
For standard class "C" LANs, the network address is the first 3 fields of this Destination IP Address. The 4th (last) field can be left at 0. |
Network Mask
|
The Network Mask used on the remote LAN segment. For class "C" networks,
the standard Network Mask is 255.255.255.0
|
Gateway
IP Address |
The IP Address of the Router on the LAN segment to which this device is
attached. (NOT the router on the remote LAN segment.)
|
Interface
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Select the appropriate interface - LAN (Internal LAN) or WAN (External LAN
or WAN) from the drop-down list.
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Metric
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The number of routers which must be traversed to reach the remote LAN
segment. The default value is 1.
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