Chapter 5

Have-A-Seat

1. DDR could be configured to dial up Atlanta from the three production facilities and provide a backup should a primary link fail. This solution would be most cost-effective as the backup lines would only be used in situations where the primary lines were unavailable. Dedicated, redundant connections could be used. They would be more expensive, and you would want to address the issue of load balancing should they be deployed.

MPS Construction

1. By deploying the three-part firewall, Mike is able to place the e-mail server in a secure location on the DMZ outside of MPS’s internal network. By using access lists on the routers, Mike is able to ensure that the only traffic leaving MPS’s internal network is to their mail server, thus denying access to other less-productive Internet resources. Mike needs to be concerned with the Enterprise Campus and the Enterprise Edge functional areas. MPS Construction’s Internet connection is shown below.

   

2. By using hierarchical design, Mike is able to simply add additional access-layer and distribution-layer devices as necessary. He will still keep the core of his network in Denver, and that will not expand or change. As new sites are added, they add into the hierarchy without having to change the existing network, which is a major benefit. Addressing issues and routing protocol configurations is also simplified.

Willow Creek School District

1. In this instance, the core layer is represented by the hub router at the District office, the distribution layer by the routers in the individual schools, and the access layer by the switches installed in the schools. As a school’s network grows, additional access layer devices are added (switches). As new schools come on line, additional distribution layer devices are added (routers). Expanding any part of the network will not require the entire internetwork to be re-engineered. A diagram of Willow Creek’s network is shown below.

   

2. Since Scott will be running TCP/IP over these two connections, he will need to ensure that he is using a routing protocol that supports load balancing like EIGRP between his routers and his ISP. Should one of the lines go down, the routing protocol will handle the failover.