Chapter 4 - RouteFinder Software
MTASR3
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IP Setup
The IP Port Setup dialog box enables you to change the IP routing capabilities, add or delete logical
WANs, enable the DHCP server, assign DNS address, and define default routes. The initial routing
capabilities were established during the software installation. However, you can change the IP routing
parameters by clicking the Advanced tab and changing, for example, the RIP Response Time or RIP
Route Aging Time. The WAN tab allows you to change the WAN port IP address, the remote address,
and if logical WAN ports are being added for frame relay, you can add them by clicking Add.
The Ethernet tab displays the parameters for your Ethernet port with the IP Address and IP Mask
established during the initial loading of the software.
The Unnumbered Link option can be selected (checked) for the WAN ports for point-to-point links.
When selected, it disables the Port Address and Remote Address groups. Unnumbered links are
useful only between two routers; in this case, local and remote. When running RIP over a PPP link,
both ends of the link must be either unnumbered or numbered with the same IP subnet. An
advantage of not assigning an IP address to each WAN port is that you conserve valuable network
and subnet numbers.
The Remote IP Address defines the IP address for the destination end of a point-to-point link and is
necessary only if the selected WAN port has been enabled for point-to-point operation. Note: the
remote IP address must fall within the same IP network as the local IP address.
The Frame Type option defines the MAC layer frame encapsulation to be used for IP transmissions
from the specified port. The Ethernet port supports Type II and SNAP frames, but the WAN ports
support only Type II frames.
In the Support group, ICMP Redirect defines if the specified port is permitted to issue an ICMP
Redirect message to the source IP address. The most likely cause of this message is the delivery of
a datagram to a router that is not on the forwarding path to the destination address. This is often due
to a wrong configuration of the IP client sending the datagram. The packet causing the ICMP
Redirect message to be transmitted is forwarded to the appropriate router.
ICMP Mask Reply enables support for nodes on the connected networks to learn their subnet
masks.
RIP enables RIP based routing on the specified port, and is normally enabled. However, RIP can be
disabled if you are using WAN links in Dial-on-Demand mode. In such links, disabling RIP will reduce
traffic on the link as this will also disable periodic RIP broadcasts. RIP routing on the port will be
automatically turned off when Dial-on-Demand is enabled in PPP port setup.
Finally, the RIP Poisoned Reverse option defines if Poisoned Reverse RIP messages are supported
on the specified port. Generation and processing of poisoned routes (RIP entries with their
