10.9 Exercises

10.9 Exercises

1. For the following primary design goals, list at least two secondary or derivative design goals. Explain your answers.

   1. Minimizing WAN costs

   2. Simplifying network management

   3. Maximizing supportability

   4. Scaling the network

      1. From LAN to WAN

      2. To double its backbone capacity

      3. To increase the number of users by 50%

2. A particular LAN network design has design goals of making the network easy to use and administer and maximizing the performance of the network by choosing the highest-performance technologies available.

   1. Explain possible trade-offs between these two design goals.

   2. Develop a simple chart that shows that trade-offs in (a) for the following technologies:

      1. Ethernet (10bT)

      2. Fast Ethernet

      3. Gigabit Ethernet

      4. FDDI

      5. ATM OC-3c

      6. ATM OC-12c

   3. Describe the requirements for network management for each of the technologies in (b), including help-desk or network operations center support.

3. Some common technology evaluation criteria are discussed in Section 10.5 and are shown below. Apply these evaluation criteria to the list of technologies in Exercise 2b.

   Technology

   Broadcast Support

   Connection Support

   Technology Functions and Features

   Performance Upgrade Paths

   Flow Considerations

4. List two other evaluation criteria in addition to those described in Section 10.5. Apply these additional evaluation criteria to the list of technologies in Exercise 2b.

5. Describe how black boxes are used to isolate areas of a network. Apply this method to the network in Figure 10.19. Show how black boxes are applied to hide each area under review and to hide the other areas.

   
   Figure 10.19: Network for Exercise 5.

6. In Figure 10.20, you are asked by the customer to make technology decisions for this network. Determine the placement of black boxes in each area to prepare to make these decisions.

   
   Figure 10.20: Network for Exercise 6.