Which of the following four designs is to be preferred?

You work as a network technician at TestKing.com. You have been assigned the
task of designing a new TestKing internetwork. The main priority is to minimize the
link costs. TestKing.at the same time wants to ensure the branch offices with direct
connectity to the main site.

A. Design TestKingA
B. Design TestKingB
C. Design TestKingC
D. Design TestKingD

Answer: C

Explanation:

Every network looks for cost efficiency. Redundancy is often sacrificed on the altar of monthly
cost. Thus, the hub and spoke Frame Relay network design is one of the more common.
In this configuration, you pick a centralized location (most likely, your largest, most
connected office) as the "hub" of the network. All other locations are considered "spokes"
and have a single virtual circuit connection back to the hub.

The major advantage of this configuration is the cost. It offers the cheapest monthly price
tag, which cost-cutting corporations enjoy. The disadvantages are beginning to mount
against this design, however. The redundancy is sorely lacking. If a single router (the
central router) loses connectivity for any reason (if the router crashes, if a trenching
company cuts through the line), your entire WAN goes down. The other disadvantage of
this design is beginning to eclipse even redundancy. It is the disadvantage of tandem
switching. Any time the spoke offices need to reach each other, they must go through the
hub office.