Take these actions before configuring your gateway.
Before you configure the gateways for your network, you
must first do the following:
Consider the number of gateways to use.
The
number of gateways you need to configure will depend upon:
The number of networks you want to connect.
How you want to connect the networks.
The level of activity on the connected networks.
For example, suppose users on Network 1, Network
2, and Network 3 all need to communicate with each other.
Figure 1. Simple gateway configuration
This illustration contains three network clouds numbered one,
two, and three. Networks one and two are connected with gateway A.
Networks two and three are connected with gateway B.
To connect
Network 1 directly to Network 2, you would use a single gateway (Gateway
A). To connect Network 2 directly to Network 3, you would use another
gateway (Gateway B). Now, assuming the proper routes are defined,
all the users on all three networks can communicate.
However,
if Network 2 is very busy, communication between Network 1 and Network
3 might suffer unacceptable delays. Furthermore, if most of the inter-network
communication occurs between Network 1 and Network 3, you might want
to connect Network 1 directly to Network 3. To do this, you could
use an additional pair of gateways, Gateway C (on Network 1) and Gateway
D (on Network 3), with a direct connection between these two additional
gateways. This may be an inefficient solution, however, because one
gateway can connect more than two networks.
A more efficient
solution would be to connect Gateway A to Gateway B directly, as well
as to Network 2. This would require a second network adapter in both
Gateway A and Gateway B. In general, the number of networks you connect
through a single gateway is limited by the number of network adapter
cards the gateway machine can support.
Decide on the type of routing to use.
If
your network is small, and its configuration rarely changes, you probably
want to use static routing. But if you have a large network whose
configuration changes frequently, you probably want to use dynamic
routing. You might decide to use a combination of static and dynamic
routing. That is, you might want to give static definitions to a few
specific routes, while allowing other routes to be updated by the
daemons. The static routes you create are not advertised to other
gateways and are not updated by the routing daemons.
If you are using dynamic routing, choose the routing daemon
according to the type of gateway you need and the protocols your gateway
must support.
If the gateway is an interior gateway, and
only needs to support RIP, choose the routed daemon.
If the gateway must support any other protocol, or is an exterior
gateway, choose the gated daemon.
Note: Unpredictable
results can occur if the gated and routed daemons
run on the same host at the same time.
