Course 2 – The Bits and Bytes Of Computer Networking

Week 5: Connecting to the Internet

Coursera Study Guide


In the fifth week of this course, we’ll explore the history of the Internet, how it evolved, and how it works today. We’ll understand the different ways to connect to the Internet through cables, wireless and cellar connections, and even fiber connections. By the end of this module, you’ll be able to define the components of WANs and outline the basics of wireless and cellular networking.

Learning Objectives

  • Describe various Internet connectivity technologies.
  • Define components of WANs.
  • Outline the basics of wireless and cellular networking.


1. Another term for POTS, or the Plain Old Telephone System, is _______________. 

  • Public Switched Telephone Exchange.
  • Phone Switched Transport Network.
  • Public Switched Telephone Network. (CORRECT)
  • Public Available Telephone Exchange.
  • Public Available Telephone Network.

Nice work! POTS and PSTN refer to the same thing.

2. A baud rate is a measurement of the number of ______________________.

  • packets that can be sent across a telephone line every second.
  • bytes that can be sent across a telephone line every second.
  • bits that can be sent across a telephone line every second. (CORRECT)
  • data segments that can be sent across a telephone line every second.

That’s right! A baud rate is equivalent to bits per second.


1. T1 is short for __________. 

  • Transmission 1.
  • Transportation 1.
  • Transportation System 1.
  • Transmission System 1. (CORRECT)

Correct! T1 is short for Transmission System 1.

2. How fast is a T1 line?

  • 1.544 Mb/sec (CORRECT)
  • 1 Mb/sec
  • 128 Mb/sec
  • 44.763 Mb/sec

You nailed it! A T1 communicates at speeds of 1.544 Mb/sec.

3. Select all statements that are true of cable internet connections.

  • They’re broadband connections. (CORRECT)
  • They’re shared bandwidth connections. (CORRECT)
  • They’re dial-up connections.
  • They’re wireless connections.
  • Nice job! A cable connection is a broadband connection.

Great work! A cable connection is a shared bandwidth connection.


1. WAN stands for ______________.  

  • Wired Area Network.
  • Wireless Area Network.
  • Wireless Local Area Network.
  • Wide Area Network. (CORRECT)

Wohoo! WAN stands for Wide Area Network.

2. In a WAN, the area between a demarcation point and the ISP’s core network is known as ___________.

  • a local loop (CORRECT)
  • a Local Area Network
  • a local link
  • an access point

Correct! A local loop is the name for the area between a demarcation point and an ISP’s network.

3. A point-to-point VPN is also known as a ______________.

  • site-to-site VPN (CORRECT)
  • one-to-many VPN
  • port forwarding VPN
  • data link VPN

You got it! A point-to-point VPN can also be referred to as a site-to-site VPN.


1. How many address fields does an 802.11 header have?

  • 1
  • 2
  • 3
  • 4 (CORRECT)

Awesome! There are four different address fields in an 802.11 header.

2. A wireless channel is ____________.

  • a collision domain.
  • an example of an ad-hoc network.
  • a portion of a frequency band. (CORRECT)
  • a point-to-point wireless connection.

Good work! A channel represents a portion of a frequency band.

3. Choose all of the frequencies that wireless networks typically operate on.

  • 88Mhz
  • 1.544Ghz
  • 2.4Ghz (CORRECT)
  • 5Ghz (CORRECT)

Right on! Many wireless networks operate on the 2.4Ghz frequency band.

Correct! Many wireless networks operate on the 5Ghz frequency band.


1. Let’s see how much you learned about wireless channels and how to select the optimal setup!

Here’s the scenario: You’re an IT Support Specialist that has setup three wireless channels for a company. As time goes on, neighboring companies have their own wireless networks coming into operation. This causes network interference between your networks and their network.

Step 1: You’ll see three wireless channels with access points that you control. These are represented by the orange bubbles on the screen. You can drag these around on the screen using the grey rectangle at the top of the bubble.

Step 2: After a few seconds, a new wireless network will appear, which is represented by a different colored bubble. This represents the competing wireless networks.

Step 3: Minimize network interference by moving your wireless channels so there’s as little overlap as possible for all wireless channels.

Step 4: Once you’ve best positioned the wireless channels, click “Submit.”

Step 5: If you successfully minimized network interference, click the “Next” button and you’ll respond to a new scenario based on your previous answer. You have 5 scenarios to complete for this activity. If your answer is wrong, click “Reset” and try again.

Scenario 1:

Course 2 Week 5.1
Coursera IT Support Certification
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Coursera IT Support Certification


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Coursera IT Support Certification


Course 2 Week 5.5
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Coursera IT Support Certification(CORRECT)


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Coursera IT Support Certification


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Course 2 Week 5.10



1. The rate at which a dial-up connection can send data across a telephone wire is known as a _____ rate.

  • Baud (CORRECT)
  • data
  • transfer
  • voice

Great job! A baud rate is equivalent to bits per second.

2. The more accurate name for a modem used for a DSL connection is a ______.

  • POTS
  • CMTS
  • ONT

You nailed it! A DSLAM is the proper name for a DSL modem.

3. A section of the radio spectrum that’s been agreed upon to be used for certain communications is known as a _______.

  • frequency band (CORRECT)
  • channel
  • collision domain
  • wireless LAN

Right on! Different locales might have different frequency bands defined.

4. A traditional wireless network involving access points that all have wired connections is known as a(n) _______.

  • LAN
  • WAN
  • ad-hoc network

Nice work! A WLAN is the term for a traditional wireless network.

5. WPA2 uses a key that’s ____ bits long.

  • 64
  • 128
  • 256 (CORRECT)
  • 512

Wohoo! 256-bit keys are pretty difficult to break.

6. Modems communicate data by using which method?

  • Light pulses
  • Audible wavelengths (CORRECT)
  • Radio frequency
  • Electric charges

Well done! Phone lines were developed to transmit sound. Modems transfer data through audible wavelengths.

7. Digital Subscriber Line (DSL) is the only Internet connection option available for a small office in the middle of nowhere. Which type will provide speeds above 1.544 megabits per second?

  • High Bit-rate Digital Subscriber Line (HDSL) (CORRECT)
  • Symmetric Digital Subscriber Line (SDSL)
  • Digital Subscriber Line Access Multiplexer (DSLAM)
  • Asymmetric Digital Subscriber Line (ADSL)

You nailed it!

8. An Internet connection problem for customers is found to be outside a carrier’s regional office. As a result, which area needs troubleshooting?

  • Core network
  • Wide Area Network (WAN)
  • Demarcation point
  • Local loop (CORRECT)

Awesome! A local loop is the portion of a network between a customer’s demarcation point and the carrier or ISP facility.

9. In which wireless configuration type do nodes communicate directly with each other, rather than with an access point?

  • 2.4Ghz
  • 802.11b
  • Ad-hoc (CORRECT)
  • Mesh network

You got it! In an ad-hoc network, all nodes communicate and transmit directly to each other.

10. Which configuration is considered to be a common way to increase security in a wireless network?

  • Wired Equivalent Privacy (WEP)
  • 5Ghz Channel
  • WiFi Protected Access (WPA)
  • Media Access Control (MAC) filtering (CORRECT)

Great work! MAC filtering only allows certain devices to connect to a network.

11. Which technology is NOT a form of broadband?

  • Cable Internet
  • Fiber
  • DSL

Nice job! ISDN is an older analog dial-up method that is faster than traditional dial-up.

12. Which connection technology uses what is known as a CMTS?

  • Digital Subscriber Line
  • Cable Internet (CORRECT)
  • Dial-up
  • Fiber optic

You nailed it! The Cable Modem Termination System (CMTS) connects lots of different cable connections to an ISPs core network.

13. What does a wireless LAN (WLAN) act as to a wired network?

  • Switch
  • Gateway
  • Bridge (CORRECT)
  • Router

Yep! A wireless Ethernet bridge allows the devices on a wired Ethernet network to connect to a wireless network. The bridge acts as the connection point to the Wireless LAN

14. An IT suspects that an unauthorized device is connected to a wireless network. This is a result of passkey sharing on a device brought from home. What is put in place to stop such activity?

  • WiFi Protected Access 2 (WPA2)
  • Media Access Control (MAC) Filtering (CORRECT)
  • Channel overlap
  • Collision domain

Yep! MAC filtering allows or disallows a device to connect to a network, based on a hardware address.

15. Which technology is used as a demarcation point for fiber optics?

  • Modem
  • Multiplexer
  • Point-to-point protocol
  • Optical Network Terminator (CORRECT)

Right on! An optical network terminator is similar to a modem and acts as a demarc for a fiber optic line.

16. Which value once represented a very popular modem baud rate that was used with dial-up connections?

  • 14400 (CORRECT)
  • 110
  • 1990
  • 1970

Nice job! While not commonly used today, dial-up still exists. 14400 (14.4k) baud was a popular baud (speed) rate.

17. The more accurate name for a cable modem is a ______.

  • POTS
  • ONT

Yep! A CMTS is the proper name for a cable modem.

18. The original and flawed wireless security protocol is known as _____.

  • WPA
  • MAC filtering
  • VPN

Correct! WEP is not very secure and has been mostly phased out.

19. WPA stands for _______.

  • WiFi Protected Access (CORRECT)
  • Wireless Protection Augmentation
  • WiFi Proxy Access
  • Wired Protected Access

You got it! WPA is an update to WEP that’s much more secure.

20. Devices that connect to the Internet are often categorized into silos. Which silo controls network traffic?

  • Phones/tablets
  • Computers/laptops
  • Servers/data centers
  • Switches/routers (CORRECT)

Well done! Switches and routers are two of many devices that control network connectivity and traffic.

21. Which wireless security standards uses a 128-bit key?

  • Wired Equivalent Privacy (WEP)
  • WiFi Protected Access (WPA2)
  • WiFi Protected Access (WPA) (CORRECT)
  • Ad-hoc

Woohoo! WPA replaced WEP. It uses a 128-bit key making it harder to crack.

22. A point-to-point virtual private network (VPN) utilizes this type of device at each point.

  • Firewall (CORRECT)
  • Multiplexer
  • Modem
  • PPPoE

Right on! Firewalls are devices that can act as a VPN endpoint.

23. A wireless network does not benefit like a wired network does, when it comes to collision reduction. Which device reduces collisions on a wired network?

  • Router
  • Gateway
  • Switch (CORRECT)
  • Hub

You nailed it! Switches remember which computers are on which physical interfaces, so traffic is only sent to the intended node.

24. What Internet system, that still exists today, was built during the early days of dial-up networking?

  • Bulletin Board System
  • World Wide Web
  • Broadband

Awesome! USENET is an early online system that was created to exchange messages.

25. How many simultaneous phone conversations can a T1 line carry?

  • 23
  • 28
  • 24 (CORRECT)
  • 20

Woohoo! A T1 is a dedicated communication line that can carry both data and voice.

26. Which of the following is NOT a Wide Area Network (WAN) connection type?

  • Asynchronous Transfer Mode (ATM)
  • Digital Subscriber Line (DSL) (CORRECT)
  • Frame Relay
  • High-Level Data Link Control (HDLC)

Well done! DSL is a broadband technology that is used for Internet connectivity.

27. What two benefits are a result of configuring a wireless mesh network? Check all that apply.

  • Range (CORRECT)
  • Ad-hoc configuration
  • Performance (CORRECT)
  • WiFi protected setup

Awesome! Range increases when access points are configured in a mesh where all points are connected to each other.

Nice job! Performance increases when access points are configured in a mesh where all points are connected to each other.

28. A T1 consists of _____ telephone channels.

  • 1
  • 24 (CORRECT)
  • 28
  • 100

That’s right! A T1 uses 24 telephone channels to send data.

29. ONT stands for ______.

  • Optical Network Telephone
  • Optional Network Traffic
  • Optical Network Tether
  • Optical Network Terminator (CORRECT)

Correct! An ONT sits between a fiber network and a more traditional copper one.

30. Another name for cellular networking is ______ networking.

  • wide area
  • organic
  • computer
  • mobile (CORRECT)

Awesome job! Depending on where you’re from, one term or the other may be more common.

31. What connection type is known as “always on”?

  • Internet
  • Ethernet
  • Plain Old Telephone System (POTS)
  • Broadband (CORRECT)

Great work! Broadband is known as an “always on” technology. This is because a connection does not have to first be initiated.

32. An 802.11 frame contains a number of fields. Which field describes the version of 802.11 that is being used?

  • Address
  • Sequence control
  • Duration
  • Frame control (CORRECT)

You nailed it! The frame control field contains a number of subfields to describe the frame and processing. This includes the version of 802.11 being used.

33. Similar to Wireless networks, cellular networks use band configuration to avoid what problem?

  • Distance
  • Overlap (CORRECT)
  • Security
  • Speed

Great work! Cell towers are configured to use bands that don’t overlap, just like WiFi uses different channels.

34. Which form of Digital Subscriber Line (DSL) features differing upload and download speeds?

  • HDSL
  • SDSL

Nice job! Asymmetric Digital Subscriber Line (ADSL) connections feature different speeds for outbound and incoming data

35. When it comes to wireless channels, which channels never overlap? Check all that apply.

  • 3
  • 1 (CORRECT)
  • 4
  • 11 (CORRECT)

You got it! Some channels are close together and may cause an overlap. Channels 1,6, and 11 are far enough apart to never overlap.

Nice job! Some channels are close together and may cause an overlap. Channels 1,6, and 11 are far enough apart to never overlap.

36. Cat5 and Cat6 cabling refer to which reference model layer?

  • Presentation
  • Transport
  • Physical (CORRECT)
  • Data link

Woohoo! Physical media, like cables, provide connectivity and are associated with the physical layer.