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Manually Configuring your Modem-Router
Manually Configuring your Modem-Router
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Authentication
Required
None: No authentication.
Password: A password authentication key is
included in the packet. If this does not match
what is expected, the packet will be discarded.
This method provides very little security as it
is possible to learn the authentication key by
watching RIP packets.
MD5: An algorithm that is used to verify data
integrity through the creation of a 128-bitmessage
digest from data input (which may be a message
of any length) that is claimed to be as unique to
that specific data as a fingerprint is to a specific
individual.
Authentication
Code
Password or MD5 Authentication key.
RIP sends routing-update messages at regular intervals and when the
network topology changes. When a Modem-Router receives a routing
update that includes changes to an entry, it updates its routing table
to reflect the new route. RIP Modem-Routers maintain only the best
route to a destination. After updating its routing table, the Modem-
Router immediately begins transmitting routing updates to inform
other network Modem-Routers of the change.
Routing Table
Description
Flags
Indicates the route status:
C = Direct connection on the same subnet.
S = Static Modem-Router
R = RIP (Routing Information Protocol) assigned
route.
I = ICMP (Internet Control Message Protocol)
Redirect route.
Network
Address
Destination IP address
Netmask
The subnetwork associated with the destination.
This is a template that identifies the address bits
in the destination address used for routing to
specific subnets. Each bit that corresponds to a
“1” is part of the subnet mask number; each bit
that corresponds to “0” is part of the host number.
Gateway
The IP address of the Modem-Router at the next
hop to which frames are forwarded.
Interface
The local interface through which the next hop of
this route is reached.
Metric
When a Modem-Router receives a routing update
that contains a new or changed destination
network entry, the Modem-Router adds 1 to the
metric value indicated in the update and enters
the network in the routing table.
