Table of Contents
Module 2 - Design the Network Structure
Section 1 - Design the Topology
Section Objectives
Upon completion of this section, you will be able to:
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Describe the advantages, disadvantages, scalability issues, and applicability
of standard internetwork topologies.
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Draw a topology map that meets the customer's needs and includes a high-level
view of internetworking devices and interconnecting media.
Time Required to Complete This Section
Approximately 4 hours
Completing This Section
Follow these steps to complete this section:
1. Study the reading assignment.
2. Click on any links that you see in the reading assignment and review
the information that appears.
3. Review any tables and job aids that appear in the reading assignment.
4. Review the case studies at the end of this section.
5. Complete the questions in each case study.
6. Review the answers provided by our internetworking experts.
Resources Required to Complete This Section
To complete this section, you will need:
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Access to the World Wide Web and Cisco's web site
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A downloaded, printed copy of this section
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Paper and pencil
Reading Assignment 1
Network Topology Models
Click to each of the following links to read information about three different
network topology models.
Reading Assignment 2 (Optional)
Design Guides
Cisco publishes some excellent design guides that will help you design
network topologies for customers. Depending on the solutions you are developing,
refer to one or more of the following guides:
Multiple-Choice Test
Answer the following network design topology questions by clicking on the
letter to the left of the correct answer.
1. The hierarchical model for internetwork design
A. alleviates concerns about internetwork
diameter.
B. defines the number of allowed hops
in an internetwork.
C. applies to large internetworks, but
not small internetworks.
D. helps a designer implement scalable
internetworks.
2. Which one of the following is an issue in large
Novell NetWare networks that use a full-mesh
Frame Relay topology?
A. Split horizon cannot be turned off.
B. SAP broadcasts use a substantial
amount of bandwidth.
C. Snapshot routing is not yet supported
to reduce bandwidth usage by IPX RIP.
D. Servers do not comply with the CIR.
3. When designing load balancing in a WAN network,
what is the most important rule?
A. Use equal-cost paths within each
layer of the hierarchy.
B. Minimize the number of hops between
sites.
C. Use Enhanced IGRP for the most effective
load balancing.
D. Use an odd number of routers (rather
than an even number).
4. Which one of the following conditions would result
in recommending routing instead of switching?
A. Many Ethernet collisions
B. Excessive number of Ethernet runt
frames (shorter than 64 bytes)
C. Bandwidth utilization over 40 percent
on Ethernet
D. Many desktop protocols sending packets
to find services
5. Which one of the following statements best describes
the specialized role that each layer of the
hierarchical model plays?
A. The access layer provides policy-based
connectivity.
B. The distribution layer provides resource
discovery services.
C. The core layer provides optimal transport
between sites.
D. The core layer provides workgroups
access to the internetwork.
6. Cisco's Hot Standby Router Protocol (HSRP)
is a useful tool for ensuring that
A. IPX and AppleTalk sessions do not
die when the default router dies.
B. IP sessions do not die when the default
router dies.
C. ATM LAN Emulation sessions do not
die when the LAN Emulation server dies.
D. Core routing does not die when floating
static routes become active.
7. In a three-part firewall security system, the
outside filter router should support
A. configuration via TFTP.
B. proxy ARP service.
C. static routing only.
D. IP route caching.
Case Studies
In this section, you will analyze the existing network and sketch a
topology based on the customer requirements.
Read each case study and complete the questions that follow. Keep in
mind that there are potentially several correct answers to each question.
When you complete each question, you can refer to the solutions provided
by our internetworking experts. The case studies and solutions will help
prepare you for the Sylvan exam following the course.
In this section, you will review the following case studies:
1. CareTaker Publications, a publishing company
2. PH Network Services Corporation, a health care company
3. Pretty Paper Ltd., a European wall covering company
4. Jones, Jones, & Jones, an international law firm
Case Study: CareTaker Publications
Click here to review the CareTaker case
study. Then answer the following questions.
In a conversation with Mr. Smith, you point out the load-sharing CSU
is not required if you bridge the traffic using the routers. You tell Mr.
Smith the Cisco IOS software features that would be a great value-add to
the bridged SNA traffic. Mr. Smith says he has already had this discussion
with the parent company. However, the parent company's network administrators
require this configuration.
1. On a separate sheet of paper, draw a topology
that will meet CareTaker’s requirements. Include only the
high-level view of
the location of links and internetworking devices. In a few sentences,
describe how your
topology meets CareTaker’s
needs.
2. After putting your initial topology together,
the IS manager has brought up the question of failures. She feels
that it is very important
that the warehouse not lose access to the mainframe and its server. In
response to your
question about the
economic trade-offs, she stated that management probably would not accept
any kind of
fail-safe or redundancy
that increases the cost more than 2 to 5 percent. What modification, if
any, would you
make to your design
to accommodate fail-safe operations of the warehouse?
Now that you have completed the exercise, click here
to view the solutions provided by our internetworking design experts.
Case Study: PH Network Services Corporation
Click here to review the PH Network case
study. Then answer the following questions.
1. Draw a topology that will meet PH Network’s
requirements. In a few sentences, describe how your topology
meets its needs.
2. PH has brought up the question of telecommunication
failures. It has had numerous failures in the lines to the
hospitals. These are
critical communications and the company would like to known if anything
can be done
to reduce the chance
of these communication losses. What modification, if any, would you make
to your design
to accommodate fail-safe
operations to the hospitals?
Now that you have completed the exercise, click
here to view the solutions provided by our internetworking design experts.
Case Study: Pretty Paper Ltd.
Click here to review the Pretty Paper case
study. Then answer the following questions.
1. Draw a topology that will meet Pretty Paper’s
requirements. In a few sentences, describe how your
topology meets Pretty
Paper’s needs.
2. The manager of Warehouse and Distribution
is concerned about PC client performance over the Frame
Relay network
to the new business software on the HP9000. What design constraints and
considerations
will you take
into account to answer these concerns?
3. How would you respond to the Sales and Marketing
organization's questions regarding someone’s ability to
get to data on the
NetWare servers or the HP9000 from the Internet?
Now that you have completed the exercise, click here
to view the solutions provided by our internetworking design experts.
Case Study: Jones, Jones, & Jones
Click here to review the Jones, Jones,
& Jones case study. Then answer the following questions.
1. Draw a topology that will meet Mr. Jones's
requirements. Include only the high-level view of the location
of links and internetworking
devices. In a few sentences, describe how your topology meets the law
firm's needs.
2. The managing partner called. She wanted to
emphasize that unauthorized workstations should not be
allowed access to
the Internet. How have you accommodated this request in your design?
Now that you have completed the exercise, click here
to view the solutions provided by our internetworking design experts.
If you are done with this section, click here
to advance to Section 2.
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