Ip Masquerading (Nat, Pat - ELSA LANCOM Office Manual

The route exists in the table with a time of '5' or '6'. The new route is then used if
it indicates the same or a better distance.
The route exists in the table with a time of '7' to '10' and thus has the distance '16'.
The new route will always be used.
The route exists in the table. The new route comes from the same router which
notified this route, but has a worse distance than the previous entry. If a router
notifies the degradation of its own static routing table in this way (e.g. releasing a
connection increases the distance from 1 to 2), the router will believe this and
include the poorer entry in its dynamic table.
RIP packets from the WAN will be ignored and will be rejected immediately. RIP packets
from the LAN will be evaluated and will not be propagated in the LAN.
The interaction of static and dynamic tables
The router uses the static and dynamic tables to calculate the actual IP routing table it
uses to determine the path for data packets. In doing so, it includes the routes from the
dynamic table which it does not know itself or which indicate a shorter distance than its
own (static) route with the routes from its own static table.
Routers without IP RIP support
Routers which do not support the Routing Information Protocol are also occasionally
present on the local network. These routers cannot recognize the RIP packets and look
on them as normal broadcast or multicast packets. Connections are continually
established by the RIPs if this router holds the default route to a remote router. This can
be prevented by entering the RIP port in the filter tables.
Scaling with IP RIP
If you use several routers in a local network with IP RIP, you can represent the routers
outwardly as one large router. This procedure is known as "scaling". A router like this,
with its supposedly inexhaustible supply of routes is created by the continual exchange
of information between the routers.

IP masquerading (NAT, PAT)

One continually growing problem for the Internet is the limited number of generally valid
IP addresses available. In addition to this, the allocation of fixed IP addresses for the
Internet by the Network Information Center (NIC) is an expensive process. What is more
obvious than having several computers share one IP address?
This particular solution is called IP masquerading. This is a procedure whereby only one
LAN router appears on the Internet with an IP address. This IP address is allocated to the
router either permanently by the NIC or temporarily by an Internet provider. All the other
computers on the network then "conceal" themselves behind this one IP address. Aside
Technical basics R35
ELSA LANCOM Office