Guide to Networking Essentials, Eighth Edition 10-1
Chapter 10
Wide Area Networking and Cloud Computing
At a Glance
Instructor’s Manual Table of Contents
• Overview
• Objectives
• Teaching Tips
• Quick Quizzes
• Class Discussion Topics
• Additional Projects
• Additional Resources
• Key Terms
• Technical Notes for Hands-On Projects
• Using Virtualization for Hands-On Projects
Guide to Networking Essentials, Eighth Edition 10-2
Lecture Notes
Overview
In Chapter 10, students will learn about the various WAN connections available, as well
as some of the technologies behind making them work. Students should be able to
describe the most commonly used WAN connections. They should also be able to
describe some of the components of these WAN connections, such as bandwidth
restrictions or functionality present. Finally, students will be introduced to three major
areas of cloud computing.
Objectives
• Describe the fundamentals of WAN operation and devices
• Discuss the methods used to connect to WANs
• Configure and describe remote access protocols
• Describe the three major areas of cloud computing
Teaching Tips
Wide Area Network Fundamentals
2. Discuss the differences between WAN and LAN connections, and who is responsible
WAN Devices
1. Introduce students to the types of devices used to establish and maintain a WAN
connection:
2. Explain to students how a modem allows a computer to communicate over lines that use
analog signals.
3. Discuss the purpose of a channel service unit/data service unit (CSU/DSU), which is to
4. Examine how a router is used in a WAN environment to forward packets and connect to
a CSU/DSU or modem. Use Figure 10-4 in your discussion.
Teaching
Tip
It’s a common misconception that cable modems aren’t truly modems, but are
CSUs/DSUs. Cable modems do, in fact, modulate and demodulate. See this link
for more information: http://www.howstuffworks.com/cable-modem.htm.
WAN Connection Methods
1. List some of the more common WAN connection methods:
a. Circuit switched
Circuit-Switched WANs
1. Familiarize students with the concept of a circuit-switched WAN, where temporary
dedicated connections are created between sender and receiver on demand.
2. Discuss how circuit-switched connections are used over the Plain Old Telephone
3. ISDN should be explored as an alternative to dial-up, although an outdated one. Define
Leased Lines
1. Describe how a leased line is used to provide dedicated point-to-point connectivity, and
2. Introduce students to the following types of leased lines:
a. T-carriers—Students should understand terms such as time division
multiplexing, fractionalization, and multiplexing. Give examples of how each of
Guide to Networking Essentials, Eighth Edition 10-4
Packet-Switched WANs
1. Discuss how a packet-switched WAN works. It should be noted that packet-switched
2. Define what a virtual circuit is, and discuss how it creates a logical connection between
3. Explore some of the defining characteristics of the X.25 technology, and discuss some
4. Frame relay should be discussed, focusing on how it works with PVCs and two
CSU/DSU devices.
5. Introduce Asynchronous Transfer Mode (ATM) to students, and elaborate on how it
6. Cover the functionality of Multiprotocol Label Switching (MLPS) and where it might
be used.
Ethernet WANs
1. Introduce students to Metropolitan Ethernet (Metro Ethernet) and Ethernet over MPLS
WANs Over the Internet
1. Discuss VPN over inexpensive Internet connections as a means of communication
between two locations. You should explain VPN’s benefits versus traditional WAN
methods:
a. Inexpensive
2. You should also discuss the disadvantages of using a VPN, such as unpredictability.
3. Use Table 10-2 to summarize WAN connection methods.
WAN Equipment
1. Discuss the equipment responsibilities a customer has when purchasing a WAN
3. Define central office, local loop, and last mile. Give examples of common equipment
that might qualify as provider equipment.
4. Explain how data circuit-terminating equipment (DCE) sends data to the local loop, and
Teaching
Tip
Students may see T3 connections referred to as DS3 and T1 as DS1. These terms
really describe the same bandwidths and have become mostly synonymous.
Wireless WAN Technologies
1. Explain to students that most WANs used to connect LANs have a wired technology.
2. Discuss characteristics of the three most common technologies for wireless WAN
connections:
a. 802.16 WiMAX
Quick Quiz 1
1. Which two layers of the OSI model do WAN technologies operate?
2. Which device creates a digital connection between a LAN device and the WAN link
from the service provider?
a. Analog modem
b. CSU/DSU
Guide to Networking Essentials, Eighth Edition 10-6
c. Router
d. Switch
3. Which WAN connection method creates a dedicated point-to-point connection from the
customer’s LAN through the provider’s network and to the destination network?
a. VPN over the Internet
b. Packet-switched
c. Leased line
d. Circuit-switched
4. What are the most common packet-switched networks?
5. What speed does a T1 dedicated line provide?
b. 1.544 Mbps
c. 3.088 Mbps
d. 64 Kbps
Remote Access Networking
1. Introduce the Routing and Remote Access Service feature included in Windows Server
Guide to Networking Essentials, Eighth Edition 10-7
Making a VPN Connection in Windows
1. Demonstrate how to set up a VPN connection inside of Windows using the Network &
Internet settings. Students should be familiar with the options available when
configuring a VPN connection.
Teaching
Tip
As a Linux alternative to Routing and Remote Access, you can use OpenVPN on
Linux to service VPN clients using SSL certificates (Note: Not compatible with
Cisco SSL VPN). OpenVPN clients are readily available for a variety of
operating systems. www.openvpn.net
Making a Dialup Connection
2. Discuss the two protocols internal to PPP:
Remote Access Networking via the Web
1. Explain that another remote access model in common use is remote control of your
desktop via a Web browser.
3. You should also mention that Microsoft offers a solution called Remote Desktop
Gateway that allows remote desktop connections via SSL. Point out that it doesn’t use a
Cloud Computing
1. Discuss how cloud computing can be used to offload IT responsibilities to servers on
the Internet.
2. Examine some of the benefits this approach has over traditional infrastructures, such as
3. List the three main categories of cloud computing:
• Software as a service
Software as a Service
2. Provide a common example, such as Google Apps or Microsoft Office 365. List some
Platform as a Service
1. Explore the use of hosted platforms, or platform as a service (PaaS), and show Azure
Infrastructure as a Service
1. Examine the use of a hosted infrastructure, or infrastructure as a service (IaaS), as a
2. Point out that IaaS differs from other hosted services because customers mostly rent the
Private Cloud versus Public Cloud
1. Discuss the differences between private cloud services vs. public cloud services. Point
Quick Quiz 2
1. Which protocol is used for dial-up and to create VPNs?
a. Point-to-point protocol
b. Point-to-point Tunneling protocol
c. Link Control Protocol
d. Network Control Protocol
2. Which protocol within PPP sets up the PPP connection and defines communication
parameters and authentication?
3. Which of the following is a computer networking model in which data, applications,
and processing power are managed by servers on the Internet?
a. Remote access
b. Virtual private networks
c. Cloud computing
d. Dial-up networking
4. Which category of cloud computing allows a company to use storage or entire virtual
servers as its need requires it?
5. Google’s AppEngine is an example of what kind of cloud computing technology?
a. Hosted applications
b. Hosted platforms
c. Hosted infrastructure
d. Hosted development
Class Discussion Topics
1. Students with some technical knowledge may already have their own VPN or remote
2. Discuss the pros and cons of private clouds versus public clouds. Include in your
Additional Projects
1. Design some scenarios of typical businesses that might need WAN connections of
Additional Resources
2. WAN Technologies Summarized
3. WANs over the Internet vs. MPLS
4. Wireless WAN Technologies
5. How Cloud Computing Works
Key Terms
For explanations of key terms, see the Glossary for this text.
➢ analog signal
➢ Dial-Up Networking (DUN)
➢ digital signal
➢ fractionalized
➢ frame relay
➢ infrastructure as a service (IaaS)
➢ Primary Rate Interface (PRI)
➢ private cloud
➢ public cloud
➢ smart jack
➢ software as a service (SaaS)
Technical Notes for Hands-On Projects