As a network administrator, you are more likely to work on a network that is already established than to design a new network from scratch. If the network lacks proper availability, intergrity, and secuurity, you will want to introduce these measures. Before making any recommendations, however, you must first examine every element of the network. In this project, you will assess a network diagram, identify the network's single points of failure, and recommend ways of imporving the network;s fault tolerance. For this project, you will need a way of recording your findings, whether on paper or on a computer.

Assume that 10 clients, in addition to any file servers, are c onnected to each switch and each acess point on both LANs. Also assume that the headquarters LAN manages backup and file storage for both offices. List 20 single points of failure in this design that could affect multiple, if not all, users. Consider each connection, device, interface, and component. (However, assume that each client will affect only one user, so do not consider laptop or smartphone failures, for example.)

If the single points of failure you listed in Step 1, which will affect the greatest number of users most severly? Which, if any, single points of failure will affect all WAN users at both locations? Which will affect all users at one location?

Of the single points of failure you listed in Step 1, which will affect the least number of users?

Of the single points of failure you listed in Step 1, which will affect a LAN service or application, but not Internet access for any WAN users?

Based on your assessments in Steps 2 through 4, rank the single points of failure in order of severity, from most severe to least severe. The issues at the top of the list should affect the most uders to the greatest extent and, consequently, deserve the greatest priority for fixing. (Some may have equal priority)

For each of the single points of failure in the list you created in Step 5, identify at least one way of mitigating the risk. For example, if you identifie the single firewall on the headquarters' LAN as a single point of failure, you might recommend duplicate firewalls, duplicate interfaces on each firewall, and using CARP to manage traffic to multiple firewalls using one IP address.

Draw a new network diagram from the WAN in Figure 14-14 that addresses the 10 most serious single points of failure that you identified in Step 5. Add whatever devices, links, or components are necessary to fully address the network's weaknesses.