Understanding the network.pdf - Back to Home

• Ease of use
• Reliability
• Control
• Security
• Efficiency
The reason static routing is so popular is because of its ease of use,
reliability, and control. UNIX/NT system administrators (who usually
get stuck with managing the IP network) are the most common
advocates of the use of static routes. System administrators love its
simplicity almost as much as they love having control over what goes
on with the systems they administer. Static routing can be set up on
most modern operating systems'TCP/IP implementations.
An administrator can build a master route table for the network and
distribute it to end-stations so the routes are added to the local table
when the system boots up. If a change is needed, the file can be
copied over the network to the end-stations, the is rebooted, and the
new route is added. Although ease of use is always an advantage, the
bigger win with using static routing table entries is the control and
reliability they provide. Because static routing tables are entered
manually, unless a is made or a hardware failure occurs, the tables
are absolutely correct. Dynamic routing protocols can fail or be
misconfigured. They also suffer from network convergence latency
and potential routing loops.
It is commonly held that static routing provides an element of security.
Fundamentally, this is true. An end-station cannot reach a network to
which it has no route. This approach is not exactly security in the
formal sense but rather, "security through obscurity." It accomplishes
the same end goal that a traditional security approach would—limiting
network availability through the use of access control lists (ACLs). But,
it does so by an obscure means (omitting routes from certain
workstations), instead of a secure one (creating an access list that
only allows certain hosts to access the network segment and reporting
when an attempt is made by an end-station that is not permitted).
Although static routing might fall short on the security side, it makes
up forit in efficiency. If static routing is anything, it is network and
router friendly. Dynamic routing protocols add to network traffic and
use memory and processor cycles on the router. With static routing,
none of the router resources are used for route acquisition and no
additional network traffic is generated by sending and receiving
dynamic routing updates.