Ist3333 - Final Exam

Front 1

A "blank" type of backbone network is a new type of architecture made possible

by intelligent, high-speed switches that assign computers to LAN segments via software,

rather than by hardware.

Back 1

Virtual LAN

Front 2

A 2-dimensional parity check can be used to:

Back 2

All answers except:

detect burst errors with a high degree of accuracy.

Front 3

A Backbone Network can be distinguished from a LAN in which of the following ways:

Back 3

Backbone networks connect several LANs.

LANs typically have lower transmission speeds than backbone networks.

Front 4

A backbone network typically connects many LANs together.

Back 4

True

Front 5

A connection is transmitting one bit per symbol. Which of the following could you use to increase the number of bits transmitted with each symbol?

Back 5

Increase the number of distinct frequencies recognized by both sender and receiver.

Increase the number of distinct amplitude levels recognized by both sender and receiver.

Front 6

A connection is transmitting too many bits per symbol, creating errors. Which of the following could you use to decrease the number of bits transmitted with each symbol?

Back 6

Decrease the number of distinct amplitude levels recognized by both sender and receiver.

Front 7

A friend tells you to "check out his really cool server" that he uses to store movies that his home theater can play.

Back 7

"Well, it stores data that can be accessed by other computers, so it is now a server."

Front 8

A layer 2 switch will retransmit a frame without changing it, but a router will alter the layer 2 header before retransmitting.

Back 8

True

Front 9

A logical circuit refers not to actual wire or wireless medium, but to the transmission

characteristics of the connection.

Back 9

True

Front 10

A networking infrastructure company repairing a severed cable is an example of working on which layer(s) of the Internet model?

Back 10

Physical Layer

Front 11

A non-profit you are consulting for is experiencing insufficient WAN transfer speeds to meet their needs.

Back 11

Switch services to an ethernet WAN that transmits at the same speed as the ATM WAN.

Install faster packet assembly/disassembly devices (PADs).

Front 12

A potential drawback of Peer-to-Peer LANs when compared to dedicated server LANs

Back 12

Peer-to-peer LANs can be more difficult to manage, especially as the number of network resources increases.

Front 13

A terminal has a display and an input device (e.g., a keyboard), but no CPU.

Back 13

True

Front 14

A thin-client architecture approach

Back 14

Gives greater control of the application logic

Front 15

A URL is not commonly found in an HTTP request.

Back 15

False

Front 16

A walkie-talkie is an example of a physical layer device that primarily uses which type of data transmission?

Back 16

Half-duplex

Front 17

ABC Corp. is an interesting start-up company. They have thirteen offices in eight different buildings located close to one another.

Back 17

Backbone Network and LAN

Front 18

Among media commonly used for data transmission, Cat5 UTP usually has the highest error rate.

Back 18

False

Front 19

An ARP message can be broadcast to all computers in a subnet to find a data link layer address.

Back 19

True

Front 20

An executive proposes decreasing IT costs by no longer leasing a SONET WAN circuit.

Back 20

This is likely to result in less predictable transmission speeds.

Front 21

An HTTP response usually contains which of the following?

Back 21

All answers.

Front 22

An incoming analog signal is sampled 8000 times per second. Every sample is described by 256 distinct amplitude levels. How many bytes are required to describe one second of the signal?

Back 22

8000

Reason: 2^8 = 256, 8 bits are needed for every sample. 8 * 8000 samples = 64000 bits, so if a sample is taken 8000 times in a second, it will require 64000 bits. There are 8 bits in a byte, so 64000 bits / 8 = 8000 bytes.

Front 23

An interviewer from a technology firm asks you what you would do to ensure high-value data sent to a phone application arrived without error. What are some good ideas you could share?

Back 23

Use a CRC to identify whether there were any errors in transmission.

Use a checksum to identify whether there were any errors in transmission.

Front 24

Application architecture refers to the way in which the functions of the application layer

are spread among clients and servers in a network.

Back 24

True

Front 25

As long as at least one software license is purchased, the software can usually legally be

installed on as many LAN computers as desired.

Back 25

False

Front 26

Assuming bit-stuffing is used, which of the following is the most reliable method of defining a frame of data?

Back 26

starting and ending flag

Front 27

Because IPv4 address space is scarce, 30% to 50% of companies connected to the internet are currently in process of transitioning their networks to IPv6.

Back 27

False

Front 28

Burst errors:

Back 28

can result from running a network cable too close to a power cable, can result from a poorly spliced fiber optic cable, can virtually always be detected using a CRC, are often caused by electromagnetic interference

Front 29

Circuit-switched WAN networks are usually pay-per-use, while dedicated circuit WAN networks are usually leased for an extended time period.

Back 29

True

Front 30

Consider a computer which does not know the IP address associated with Google.com, and

Back 30

Sending the message to the local DNS server, which currently DOES have the Google.com IP address listed in its table.

Sending the message to the local DNS server, which currently DOES NOT have the Google.com IP address listed in its table.

Front 31

Consider a WAN that has four interconnected locations: A, B, C, and D. Which WAN

architecture would most likely provide the best reliability-to-cost ratio for this scenario?

Back 31

partial mesh

Front 32

Consider the address 10.0.0.1/16. Which of the following statements about this address are correct?

Back 32

The subnet mask for this address is 255.255.0.0.

To fully represent this in binary, you would need 2 sets of 4 bytes, or 8 bytes in total.

This is actually an IP address and subnet mask.

Front 33

Convert the following byte to decimal:

00001001

Back 33

None of these answers are correct.

Front 34

CSMA/CA is unlike CSMA/CD in which of the following ways?

Back 34

CSMA/CA is better than CSMA/CD at preventing transmission errors.

CSMA/CA is better to use than CSMA/CD when you expect a lot of interference in a shared medium and many simultaneous hosts transmitting continually on that medium.

CSMA/CA is generally used for wireless LANs, while CSMA/CD is not commonly used for wireless LANs.

Front 35

Ethernet is an example of a network layer protocol.

Back 35

False

Front 36

For domain name resolution to work properly, what is the maximum number of domain names that can be associated with a single IP address?

Back 36

as many as you want

Front 37

For most LANs, a single server can host more than one NIC, but a single client may have only NIC.

Back 37

False

Front 38

Forward Error Correction is:

Back 38

None of these answers are correct.

Front 39

Fragment-free switching mode refers to:

Back 39

A network switch retransmitting each frame after its frame header is read.

Front 40

Given that a class C address uses the first 3 octets to define the network and only the last octet to define the host ID, how many hosts can there be on a class C network?

Back 40

254

Front 41

hexidecimal F (converted to decimal) + hexidecimal E (converted to decimal) =

"blank" in decimal.

Back 41

29

Front 42

How are frame relay services different from ATM services?

Back 42

Frame relay tends to operate at lower speeds.

Frame relay is less expensive.

Front 43

ICANN

Back 43

Approves assignment of public IP address space to organizations.

Front 44

If a single network has 254 nodes (computing devices), "blank" of those nodes can be

server(s).

Back 44

254

Front 45

If DHCP were used in a particular subnet, which of the following could you correctly infer?

Back 45

The IP addresses of hosts on the subnet have an expiration date.

A DHCP server is set up on the subnet to respond to requests for IP addresses.

Front 46

If the physical topology of a network is a star configuration, the logical topology might be a bus configuration.

Back 46

True

Front 47

If you are protecting a WLAN against experienced hackers, you shouldn't hide your Wi-Fi SSID.

Back 47

True

Front 48

If you were to look at a server farm, you would see which of the following?

Back 48

Racks of computers

Front 49

In a multipoint circuit configuration, each computer has a dedicated circuit between itself and each of the other computers in the network.

Back 49

False

Front 50

In Manchester encoding, voltage changes from low to high or high to low in the middle of the signal.

Back 50

True

Front 51

In the Internet Model, a student is interacting with the network at the application layer when she/he performs which of the following tasks?

Back 51

All answers, except:

Cuts the cable connecting him or her to the network

Front 52

In the U.S., the data rate for a T1 circuit is:

Back 52

1.5 Mbps

Front 53

MAC is a Data Link Layer function.

Back 53

True

Front 54

Networks that are designed to connect similar computers that share data with one another as opposed to relying on one machine always acting as a server are called:

Back 54

peer-to-peer networks

Front 55

One of the real costs of maintaining racks of servers, routers, and switches is keeping the equipment cool.

Back 55

True

Front 56

RIP compares to OSPF in which of the following ways?

Back 56

RIP considers the next hop, while OSPF considers the entire network topology

Front 57

STDM can be used to allow 13 computers to share 6 circuits.

Back 57

True

Front 58

Stop-and-wait ARQ is the same as Continuous ARQ in which of the following ways?

Back 58

Both use NAK messages.

Both are error control techniques.

Both use ACK messages.

Front 59

The backbone network (BN) architecture layer that is closest to the users is the:

Back 59

Access layer

Front 60

The Internet was started by the U.S. Department of defense in 1969 as a network of four

computers called "blank".

Back 60

ARPANET

Front 61

The signal bars on a wireless device such as a mobile phone or tablet typically reflect signal-to-noise ratio.

Back 61

False

Front 62

The "T" in 1000Base-T refers to the type of wire that is used.

Back 62

True

Front 63

Three companies are advertising "high" data rates, all at roughly the same prices. When you look deeper into their offerings, you discover different features. Rank the companies in order from highest to lowest data transmission rate:

Back 63

X, Y, Z

Front 64

To get more bandwidth in a digital transmission, you can do which of the following?

Back 64

Increase the range of frequencies used.

Front 65

To send four bits per symbol using amplitude modulation, you would need to assign

"blank" different amplitude levels.

Back 65

16

Front 66

UDP is unlike TCP in that it provides less assurance that a sent message will actually be

received.

Back 66

True

Front 67

Under which circumstances would you use a hub on your LAN as opposed to a router or switch?

Back 67

When you want all traffic on the LAN to be viewable by all other devices on the LAN.

When you need a LAN but can't afford a switch or router--a hub is cheaper than both of those.

Front 68

Unipolar digital signaling is better than bipolar digital signaling because it uses more distinct signals.

Back 68

False

Front 69

Users in your network are complaining that at certain times in the day, "the network

slows down."

Back 69

Increase the processing speed of the router that handles the high-priority traffic.

Split the network into parts, isolating high priority traffic on its own subnet.

Implement QoS at the transport layer.

Front 70

What are the key differences between IPv4 and IPv6?

Back 70

All answers except:

IPv4 will likely be virtually eliminated in the next 5-10 years, while IPv6 will likely have almost completely taken over by that time.

Front 71

What is the minimum number of IP addresses required for the following internetwork?

Back 71

20

Front 72

What is the optimal frame size for data transmission in an internetwork?

Back 72

All of these are correct.

Front 73

What is unique about the following IP address ranges?

Back 73

These are private address spaces that can not be used for devices on the Internet.

Front 74

When a collision happens when using CSMA/CD for MAC, a jamming signal is sent to all hosts on the circuit.

Back 74

True

Front 75

When a user accesses their email using a web browser, email contents are transferred from a server to the browser using SMTP.

Back 75

False

Front 76

When all bits of a character are transferred one after another, the bits are transferred in mode.

Back 76

serial

Front 77

When converting and transmitting analog video through a digital high-speed connection you notice the receiving end has a significant drop in picture and sound quality.

Back 77

Increase the sample rate and increase the bit rate.

Front 78

Which of the following accurately describe characteristics of data link layer "stuffing?"

Back 78

The stuffing sequence could be a single bit or multiple bits, Stuffing increases the length of the original data, and The receiver of a frame has to de-stuff any stuffing.

Front 79

Which of the following accurately describe the meaning of 10?

Back 79

All answers except:

10 in binary is equivalent to 2 in decimal.

10 in hexadecimal means the same thing as 10 in decimal.

Front 80

Which of the following accurately describe the meaning of 11?

Back 80

11 in decimal is equal to 000000000001011 in binary.

If you subtract two from 11 in decimal, then convert the result to hexadecimal, you get 9.

11 in hexadecimal can be transmitted using less than 1 byte of binary data.

Front 81

Which of the following actions will increase protection against wardriving?

Back 81

All answers.

Front 82

Which of the following activities must occur to establish a transport-layer connection using TCP?

Back 82

The receiver transmits a SYN-ACK.

The sender transmits a SYN.

The sender transmits an ACK.

Front 83

Which of the following are accurate statements about an n-tiered architecture?

Back 83

An n-tiered architecture may split up the application logic across more than one server.

An n-tiered architecture is generally more scalable than a three-tiered architecture.

Front 84

Which of the following are correct statements about client-server architectures?

Back 84

They cannot connect computers that use different hardware.

They are one of the least-used network architectures today.

They were the earliest type of network architecture.

They assign the responsibility for the presentation logic to the server.

Front 85

Which of the following are important factor(s) to consider when selecting media to be used in a network?

Back 85

Cost, Transmission Distance, Security and Speed

Front 86

Which of the following are part of TCP/IP?

Back 86

IGMP, ICMP, IP, and TCP

Front 87

Which of the following are examples of protocols that are part of the application layer in the Internet Model?

Back 87

SMTP, HTTP, and POP

Front 88

Which of the following can provide fault tolerance for the storage space on a server?

Back 88

RAID

Front 89

Which of the following connections use guided media to send and receive data on a network?

Back 89

A cable connection, A fiber-optic connection

Front 90

Which of the following correctly compare and contrast CRCs and checksums?

Back 90

Using the checksum method to look for errors, an error is assumed if the mathematical calculation ends, etc.

In a transmission, a checksum and a CRC are both just an extra string of bits tacked onto a message.

Both CRC and checksum approaches are more effective than parity checks.

Front 91

Which of the following frequencies are classified as "open" or unlicensed spectrum in the United States?

Back 91

900 Mhz, 5 Ghz, 87.9 - 107.9 Mhz, 2.4 Ghz

Front 92

Which of the following groups are involved in creating, identifying, accepting, or establishing network protocol standards?

Back 92

IEEE-SA

Front 93

Which of the following is NOT true about layer-2 switched Ethernet?

Back 93

All of these are NOT true.

Front 94

Which of the following is the most accurate response to the question, "What is the most

common default IP address for a switch?"

Back 94

None of these answers are correct.

Front 95

Which of the following methods will help prevent errors due to attenuation?

Back 95

Use a repeater or amplifier.

Front 96

Which of the following statements about ARP and MAC are correct?

Back 96

ARP is a protocol on the Network Layer, while MAC is a concept that is part of the Data Link Layer.

ARP uses IP addresses to discover MAC addresses.

The windows command "arp -a" will result in a list of MAC addresses and IP addresses.

Front 97

Which of the following statements about email are correct?

Back 97

SMTP is an email transfer protocol that operates at the application layer.

SMTP natively permits the transfer of text only.

Front 98

Which of the following statements about VLANs are correct?

Back 98

The switches in a VLAN will sometimes modify an Ethernet frame.

A VLAN allows segmentation of a network based on logical divisions (e.g., Accounting department, R&D department) rather than physical divisions

(e.g., Building 1, Building 2).

Using a VLAN is one way to segment a broadcast domain.

Front 99

Which of the following statements are correct?

Back 99

To encode a digital signal on an analog wave, you could use a modem.

To send multiple signals on the same medium, you could use FDM.

To send multiple signals on a single frequency, you could use TDM.

To encode an analog signal into a digital format, you could use a codec.

The height of a wave is called its amplitude.

The length of a wave is called its frequency.

Front 100

Which of the following statements are correct?

Back 100

To send multiple signals on a single frequency, you could use TDM.

The length of a wave is called its frequency.

(and all answers between)

Front 101

Which of the following would be more effectively sent via multicast versus unicast?

Back 101

Sending a video to all computers on a network

Front 102

Which of these is NOT a function of the physical layer?

Back 102

providing error-free transmission of data

Front 103

Your company has just added several locations in different parts of the country, and is interested in leasing circuits for a WAN.

Back 103

"Compared to a ring architecture, a star architecture is more likely to stay functioning if more than one circuit fails."

"Unlike a ring architecture, a star architecture depends on a central computer to operate."

"If we really care about reliability, we should forget about star and ring architectures and look for a way to implement a mesh architecture."

"The architecture of a WAN can affect its reliability."