Syngress - Eleventh Hour Network+ Exam N10-004 Study Guide (11 ...

Network Devices 47
There are a few situations in which integrating static and dynamic routers is
acceptable:
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When you have a router at either end of a slow WAN link, you may wish
to use static routes. These routers will not increase traffic by broadcasting
updated route information to the router on the other end of the link.
When you require a packet to travel the same path each time to a remote
network, you will need to use static routes. Add the path you would like the
packet to take to reach the destination network. You cannot enter the entire
path over several routers, only the path to the first router.
When you want to configure a static router to point toward a dynamic router
to take advantage of the dynamic router indirectly. This is the next best thing
to using a dynamic router. You can hand off the packet to the dynamic router
and let this router determine the most efficient path to the destination based
on the paths it has learned from neighboring dynamic routers.
EXAM WARNING
Routers operate at the network layer of the OSI model. The exam will deal with questions
regarding both routers and the OSI model.
Switching Routers
Switching routers have the capability to perform the tasks normally associated
with other devices. A Layer 3 switch has the capability to open packets and view
the IP address and MAC address of the computer the packet is destined for. The
switch can then review routing tables on the switch to determine the best route
to send the data. By performing these functions, the switch is able to do the work
of a router and get the packet to its intended destination by using the best route.
SECURITY INTEGRATION
The need for security in network devices and networks in general continues to
grow. Equipment and software can be added to a network, which can work with
existing devices to protect your LAN and its data.
DID YOU KNOW
A firewall protects a secure internal network from a public insecure network. Firewalls
have the capability to control the traffic that is sent from an external network, such as
the Internet, to an internal network or local computer. Firewalls use advanced techniques
to monitor connections, log potential intrusions, and act upon these incidents.
A firewall compares traffic to a set of rules that define how the traffic should be dealt with
by the firewall. If the traffic matches the rules for acceptable data, the traffic is passed on
to the network. If the rule specifies that the data be denied, the traffic will be discarded.
The following are some possible architectural implementations: