SSD8-1
.docSee section 1.1.5 of the course notes.
--------------------------------------------------------------------------------
10.
Which of the following parameters can be specified in the header of a request in the Hypertext Transfer Protocol (HTTP)?
The types of image formats that a browser understands
The type of browser (e.g., Netscape, Internet Explorer) making the request
The method by which the request is to be satisfied—for example, whether the request is a GET of a form submission
(a) I, II, and III
(b) II and III only
(c) I and II only
(d) III only
Correct answer is (a)
Your score on this question is: 0.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
View Assessment Result: Multiple-Choice Quiz 1
Your performance was as follows:
1.
The Maximum Transfer Unit (MTU) is a parameter of
(a) the technology of the physical network
(b) the operating system
(c) the size of data sent by the application
(d) the application protocol
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
2.
In a broadcast network
(a) only the computers that are tuned to a channel see and process the packets in that channel
(b) all computers see and process the application data within all packets
(c) only the destination computer sees a packet
(d) all computers see all packets, but the application data in each packet is only processed by the destination computer
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
3.
When you connect your computer to the Internet, the protocol(s) your computer uses is (are) selected according to
(a) which operating system is running on your computer
(b) the application client and server you use at each moment
(c) what vendor your Internet service provider purchased equipment from
(d) which HTTP (Web) server you connect to
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
4.
Ethernet (IEEE 802.3) is an example of
(a) an a priori standard
(b) a standard developed by the International Telecommunications Union
(c) a de facto standard later developed into a de jure standard
(d) a successful example of the Internet's strategy of developing standards through "rough consensus and running code"
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.1.6 of the course notes.
--------------------------------------------------------------------------------
5.
Two packets A and B are sent in that order through a connection-oriented communication network. They could arrive at the destination
(a) in any order, after possibly having traversed different routes
(b) only in the order A-B, after having traversed the same route
(c) only in the order A-B, after possibly having traversed different routes
(d) in any order, after having traversed the same route
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.2 of the course notes.
--------------------------------------------------------------------------------
6.
A packet with no data is sent from host A to host B on an otherwise idle network. The packet is found to have taken 35 milliseconds to reach B. The incremental overhead to send an additional byte (usually called the "throughput") is estimated to be five microseconds by repeatedly measuring the transmission times of long packets. Approximately, how long will an eight Kbytes (8192 bytes) packet take to reach B when sent from A?
(a) cannot be determined from the information given
(b) 76 milliseconds
(c) 55 milliseconds
(d) 40 milliseconds
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.4 of the course notes.
--------------------------------------------------------------------------------
7.
You have recently become the first network engineer of a large corporation with offices worldwide. The company is considering the installation of a data network, but the Board of Directors is rather old-fashioned and does not see the need to change the company's time-honored business practices. Your first task at the job is to justify your salary and the cost of a new network, and for this purpose you are about to give a presentation to the Board of Directors. Which of the following would you include in your presentation? Assume the directors are extremely intelligent, though perhaps not knowledgeable in your field.
Lower expenditures on computer hardware
Higher availability of customer services
Better protection of the company's proprietary information
(a) II only
(b) II and III
(c) I and II only
(d) I and III only
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.1 of the course notes.
--------------------------------------------------------------------------------
8.
_____ can be used to measure latency in the communication network.
(a) Bit Error Rate
(b) Throughput
(c) Percentage of packets retransmitted
(d) Roundtrip time
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.1.4 of the course notes.
--------------------------------------------------------------------------------
9.
An advantage of defining network protocols through agreement among many companies and individuals is that
(a) different implementations can then communicate with each other
(b) a protocol designed by committee always has better performance than that designed by a single company or research project
(c) otherwise source code would need to be shipped with all networking applications
(d) only one implementation need then be created
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
10.
Which of the following pairs of entities name a client and one of its servers?
Google search engine/www.example.com
Web browser/Google search engine
Email client/Web browser
(a) II only
(b) I and II only
(c) I, II, and III
(d) II and III only
Correct answer is (b)
Your score on this question is: 0.00
Feedback:
See section 1.1.1 of the course notes.
(d) The search engine also has to search other servers.
--------------------------------------------------------------------------------
View Assessment Result: Multiple-Choice Quiz 1
Your performance was as follows:
1.
The throughput of a network link for an HTTP session is measured in two ways. Measurement A is the total amount of data received by the browser, divided by the duration of the session. Measurement B is the total amount of data received by the operating system on behalf of the browser, divided by the duration of the session. Which of the following statements about A and B is true?
(a) B is equal to A
(b) A is smaller than B
(c) B and A are not related
(d) B is smaller than A
Correct answer is (b)
Your score on this question is: 0.00
Feedback:
See section 1.1.4 of the course notes.
--------------------------------------------------------------------------------
2.
Which of the following methods are invoked by a server implemented with sockets?
connect( )
listen( )
accept( )
(a) III only
(b) II and III only
(c) II only
(d) I, II, and III
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
3.
We send a packet from host A to host B, which immediately acknowledges it. We measure the interval between the time the packet is sent by A and its acknowledgement is received. This interval is found to be 180 milliseconds. What can be said about the latency of the link from A to B?
(a) It is greater than 180 ms.
(b) It is exactly 180 ms.
(c) It is exactly 90 ms.
(d) It is smaller than 180 ms.
Correct answer is (d)
Your score on this question is: 0.00
Feedback:
See section 1.1.4 of the course notes.
--------------------------------------------------------------------------------
4.
All store-and-forward networks are
(a) connection-based networks
(b) broadcast networks
(c) packet or message switched networks
(d) connectionless networks
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
5.
In contrast to standards developed by traditional standards organizations like the International Telecommunications Union (ITU) or the International Standards Organization (ISO), standards developed by the Internet Engineering Task Force (IETF) can be
(a) developed in secret by the members of the IETF until the standards mature sufficiently to withstand public criticism
(b) modified arbitrarily by the Advance Research projects Agency (ARPA) of the United States Department of Defense, which originally developed the Internet
(c) applied before they have been embodied in working implementations, in order not to delay progress
(d) extensively critiqued and modified by individuals, without requiring them to have special membership status
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.1.6 of the course notes.
--------------------------------------------------------------------------------
6.
The Maximum Transfer Unit (MTU) is a parameter of
(a) the application protocol
(b) the technology of the physical network
(c) the size of data sent by the application
(d) the operating system
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.1 of the course notes.
--------------------------------------------------------------------------------
7.
A packet with no data is sent from host A to host B on an otherwise idle network. The packet is found to have taken 35 milliseconds to reach B. The incremental overhead to send an additional byte (usually called the "throughput") is estimated to be five microseconds by repeatedly measuring the transmission times of long packets. Approximately, how long will an eight Kbytes (8192 bytes) packet take to reach B when sent from A?
(a) 40 milliseconds
(b) cannot be determined from the information given
(c) 76 milliseconds
(d) 55 milliseconds
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.1.4 of the course notes.
--------------------------------------------------------------------------------
8.
A computer sends 100 Kbytes of aggregate data to another computer through the network. If this transmission time takes 10 seconds and setup time is negligible, the throughput of this network is
(a) exactly 10 Kbps
(b) in the range from 60 to 120 Kbps (kilobits per second)
(c) not able to be determined with the information given
(d) in the range from 6 to 12 Kbps (kilobits per second)
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.4 of the course notes.
--------------------------------------------------------------------------------
9.
Two packets A and B are sent in that order through a connectionless communication network. They will arrive at the destination
(a) in any order, after having traversed the same route
(b) in any order, after possibly having traversed different routes
(c) in the order A-B, after possibly having traversed different routes
(d) in the order A-B, after having traversed the same route
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.1.2 of the course notes.
--------------------------------------------------------------------------------
10.
John is using his bank's Web server to pay his telephone bill electronically. Which kind(s) of network interaction take(s) place in this Scenario, from the moment John logs into his bank's Web site until the telephone company receives the money?
People-people
People-computer
Computer-computer
(a) III only
(b) II only
(c) I, II, and III
(d) II and III only
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.1 of the course notes.
--------------------------------------------------------------------------------
Go to top of assessment.
Total score: 80.00
? Copyright 2003 iCarnegie, Inc. All rights reserved.
1.
Collision Detection improves the throughput of multiple access networks because
it can shorten the length of garbled frames
it can decrease the number of garbled frames
it delays by a random amount of time when a collision is detected
(a) I only
(b) II and III only
(c) I, II, and III
(d) I and II only
Correct answer is (d)
Your score on this question is: 0.00
Feedback:
See section 1.2.4 of the course notes.
(c) Choice III is true regardless of whether or not collision detection is used.
--------------------------------------------------------------------------------
2.
What is the type of an "8+1" parity code that outputs 100101011?
(a) Even Parity
(b) Cannot tell since we do not know which bit is the parity bit
(c) Null Parity
(d) Odd Parity
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
3.
When the data link layer applies "framing" to the data to be transmitted, it
(a) enhances it with extra data that permits the receiver to synchronize with the sender
(b) inserts flags to draw attention to high-priority data within a transmission
(c) cuts out the headers from higher layer protocols before transmission
(d) adds the protocol headers from higher layers to the data before it transmits it
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
4.
A cable is rated at 19200 baud. A 19200 baud cable is guaranteed to transmit a signal successfully that has the potential to change 19200 times per second. The maximum throughput of this cable, assuming a sensible encoding,
(a) can be any number greater than or equal to 19200 bits per second, depending on the way the data is encoded into signal voltages
(b) is between 19200 and 38400 bits per second, depending on the bit pattern of the transmitted data
(c) is exactly 19200 bits per second
(d) is less than 19200 bits per second
Correct answer is (a)
Your score on this question is: 0.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
5.
A fiber optic is found to be able to deliver light cleanly in a frequency range 25,000 GHz wide. This fiber can be used to create the following type of channel between two routers
a single 50 terabits per second (Tbps = 1,000 Gbps) data channel
5 2-Gbps data channels
one video channel but no data channels, because data cannot be encoded in light beams
(a) I only
(b) I and II only
(c) III only
(d) II only
Correct answer is (d)
Your score on this question is: 0.00
Feedback:
See section 1.2.1 of the course notes.
(b) The electronics that interface to the fiber cannot process more than a few GHz of bandwidth in a single channel.
--------------------------------------------------------------------------------
6.
A packet-switched network uses switches that schedule packets using a first-in-first-out (FIFO) discipline. Several people want to carry out a conference over this network. The conference is carried out via typed text for the most part, but, occasionally, one of the parties has to send a large video. This happens very rarely. Which of the following switching approaches is most suitable for this application?
(a) Message-switched
(b) Space-switched
(c) Circuit-switched
(d) Packet-switched
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.2.3 of the course notes.
--------------------------------------------------------------------------------
7.
Which of the following are responsibilities of the data link layer?
Noticing transmission errors
Regulating transmission speed when a receiver is overwhelmed
Regulating transmission speed when any of several IP routers in a network path are overwhelmed
(a) I only
(b) I and II only
(c) I, II, and III
(d) II and III only
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
8.
A specific CSMA-CD network such as 10-BASET "Ethernet"
(a) can connect very distant nodes
(b) has higher cost per node as nodes are added
(c) suffers performance degradation as nodes are added
(d) works best for an even number of nodes
Correct answer is (c)
Your score on this question is: 0.00
Feedback:
See section 1.2.4 of the course notes.
--------------------------------------------------------------------------------
9.
A university has 20 computers in a laboratory that is currently served by several small 10 Base-T "Ethernet" hubs. The network performance has been found to be lacking, and an upgrade is planned. The computers usually have modest network needs (in the order of 500 Kbps), but one or two are occasionally used to receive high-quality remote video streams that require in the order of 10 Mbps. No more than two computers are used for this purpose at any given time, but any two may be used for this application. What would you suggest for the upgrade?
(a) Replace the hubs with 100 Base-T hubs
(b) Replace the hubs with 10 Base-T switches
(c) A 10 Base-T bridge to connect several existing hubs
(d) A new bank of dial-up modems
Correct answer is (a)
Your score on this question is: 0.00
Feedback:
See section 1.2.4 of the course notes.
(c) This will not provide enough bandwidth for the video application to any computer.
--------------------------------------------------------------------------------
10.
The point-to-point (PPP) protocol
can only be used in analog dial-up connections
is a data-link protocol
can only be used to carry IP over serial lines
(a) II only
(b) III only
(c) I and II only
(d) II and III only
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.5 of the course notes.
1.
If you have seen any mobile telephone antennas, you will have noticed that they have groups of radiating elements facing different directions. Most antennas we know are arranged in a triangle, so that each group spans a 120-degree arc of the horizon, but we have also seen squares in which each group spans a 90-degree arc instead. There is one such arrangement for each cell of a mobile phone system. This sort of base station is unsightly and expensive. A cell could instead use a single omnidirectional antenna that would be simple and inconspicuous. Why do you think the more complicated designs are used?
(a) To decrease frequency reuse without the need for time-division multiplexing
(b) To increase frequency reuse without having to build more antenna towers
(c) To decrease the number of times a call must be handed off from one base station to another.
(d) To allow the use of switches based on space-division multiplexing
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.6 of the course notes.
--------------------------------------------------------------------------------
2.
What is the type of an "8+1" parity code that outputs 100101011?
(a) Cannot tell since we do not know which bit is the parity bit
(b) Odd Parity
(c) Even Parity
(d) Null Parity
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
3.
A parity code is a(n)
(a) fair resource allocation scheme
(b) duplex transmission technique
(c) error-correcting code
(d) error-detecting code
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
4.
After the phone company installs a T1 trunk to an office building, which of the following can it provide to the tenants of the building? Recall that a T1 trunk has a capacity of 1.544 Mbps, and that a voice channel requires an isolated 3 KHz channel.
20 new telephone lines and a 200 Kbps digital data channel
A single 1.1 Mbps data channel
25 new telephone lines
(a) I, II, and III
(b) none
(c) II only
(d) I and II only
Correct answer is (d)
Your score on this question is: 0.00
Feedback:
See section 1.2.1 of the course notes.
(a) When multiplexing several channels on a single medium, we need to allow for filter imperfections by allowing guard bands. Thus, while voice can be carried in a 3 KHz, we need to apportion a lot of bandwidth to guard bands and other overhead.
--------------------------------------------------------------------------------
5.
In contrast to message switching, packet switching
needs to find a "copper" path to the receiver before transmitting any data
offers a better upper bound on transmission delay
suffers from greater overhead at the endpoints
(a) I and III only
(b) II and III only
(c) II only
(d) I and II only
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.3 of the course notes.
--------------------------------------------------------------------------------
6.
In contrast with wireless communication, "wired" communication
does not suffer from attenuation and interference
can use any frequencies without a license
always has more throughput
(a) I and III only
(b) none
(c) II only
(d) I, II, and III
Correct answer is (c)
Your score on this question is: 0.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
7.
A fiber optic is found to be able to deliver light cleanly in a frequency range 25,000 GHz wide. This fiber can be used to create the following type of channel between two routers
a single 50 terabits per second (Tbps = 1,000 Gbps) data channel
5 2-Gbps data channels
one video channel but no data channels, because data cannot be encoded in light beams
(a) III only
(b) I only
(c) II only
(d) I and II only
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
8.
A university has 20 computers in a laboratory that is currently served by several small 10 Base-T "Ethernet" hubs that are directly connected to each other. The network performance has been found to be lacking, and an upgrade is planned. The computers are identical and place a comparable load on the network that is relatively constant and modest for each computer (in the order of 500 Kbps). What would you suggest for the upgrade?
(a) Replace the hubs with 10 Base-T switches
(b) Replace the hubs with 100 Base-T hubs
(c) A small 10 Base-T switch to connect the existing hubs
(d) A new bank of dial-up modems
Correct answer is (c)
Your score on this question is: 0.00
Feedback:
See section 1.2.4 of the course notes.
(b) This is expensive and is not necessary because each computer never uses more than the capacity of a 10 Mbps network.
--------------------------------------------------------------------------------
9.
Radio stations are able to share the AM (Amplitude Modulation) spectrum by using _____ multiplexing
(a) phase shift
(b) time-division
(c) frequency-division
(d) wavelength-division
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
10.
A cable is rated at 19200 baud. A 19200 baud cable is guaranteed to transmit a signal successfully that has the potential to change 19200 times per second. The maximum throughput of this cable, assuming a sensible encoding,
(a) is between 19200 and 38400 bits per second, depending on the bit pattern of the transmitted data
(b) can be any number greater than or equal to 19200 bits per second, depending on the way the data is encoded into signal voltages
(c) is exactly 19200 bits per second
(d) is less than 19200 bits per second
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.1 of the course notes.
1.
A fiber optic is found to be able to deliver light cleanly in a frequency range 25,000 GHz wide. This fiber can be used to create the following type of channel between two routers
a single 50 terabits per second (Tbps = 1,000 Gbps) data channel
5 2-Gbps data channels
one video channel but no data channels, because data cannot be encoded in light beams
(a) I only
(b) II only
(c) III only
(d) I and II only
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
2.
A university has 20 computers in a laboratory that is currently served by several small 10 Base-T "Ethernet" hubs. The network performance has been found to be lacking, and an upgrade is planned. The computers usually have modest network needs (in the order of 500 Kbps), but one or two are occasionally used to receive high-quality remote video streams that require in the order of 10 Mbps. No more than two computers are used for this purpose at any given time, but any two may be used for this application. What would you suggest for the upgrade?
(a) A new bank of dial-up modems
(b) Replace the hubs with 10 Base-T switches
(c) A 10 Base-T bridge to connect several existing hubs
(d) Replace the hubs with 100 Base-T hubs
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.2.4 of the course notes.
--------------------------------------------------------------------------------
3.
When a student in Hong Kong uses her computer to have a voice conversation with a teacher in Pittsburgh, the application she uses requires that the network deliver bits at a modest but constant bit rate. This is because, even though voice can be faithfully encoded in less than 64 Kbps, the late arrival of a voice sample produces a noticeable and unpleasant sound effect. Which of the following switching options will give you better quality?
(a) Circuit-switched
(b) Packet-switched
(c) Space-switched
(d) Message-switched
Correct answer is (a)
Your score on this question is: 0.00
Feedback:
See section 1.2.3 of the course notes.
--------------------------------------------------------------------------------
4.
What is the type of an "8+1" parity code that outputs 100101011?
(a) Null Parity
(b) Cannot tell since we do not know which bit is the parity bit
(c) Odd Parity
(d) Even Parity
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
5.
Which of the following are responsibilities of the data link layer?
Noticing transmission errors
Regulating transmission speed when a receiver is overwhelmed
Regulating transmission speed when any of several IP routers in a network path are overwhelmed
(a) I, II, and III
(b) I only
(c) II and III only
(d) I and II only
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
6.
If you have seen any mobile telephone antennas, you will have noticed that they have groups of radiating elements facing different directions. Most antennas we know are arranged in a triangle, so that each group spans a 120-degree arc of the horizon, but we have also seen squares in which each group spans a 90-degree arc instead. There is one such arrangement for each cell of a mobile phone system. This sort of base station is unsightly and expensive. A cell could instead use a single omnidirectional antenna that would be simple and inconspicuous. Why do you think the more complicated designs are used?
(a) To decrease frequency reuse without the need for time-division multiplexing
(b) To allow the use of switches based on space-division multiplexing
(c) To increase frequency reuse without having to build more antenna towers
(d) To decrease the number of times a call must be handed off from one base station to another.
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.6 of the course notes.
--------------------------------------------------------------------------------
7.
A parity code is a(n)
(a) error-correcting code
(b) error-detecting code
(c) fair resource allocation scheme
(d) duplex transmission technique
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
8.
After the phone company installs a T1 trunk to an office building, which of the following can it provide to the tenants of the building? Recall that a T1 trunk has a capacity of 1.544 Mbps, and that a voice channel requires an isolated 3 KHz channel.
20 new telephone lines and a 200 Kbps digital data channel
A single 1.1 Mbps data channel
25 new telephone lines
(a) none
(b) I, II, and III
(c) I and II only
(d) II only
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
9.
The maximum binary data throughput of a cable that cleanly transmits a range of frequencies up to 100 MHz is
(a) currently 56 Kbps but more as modem technology improves
(b) exactly 200 megabytes per second
(c) within 80 and 120 megabits per second
(d) exactly 200 megabits per second
Correct answer is (d)
Your score on this question is: 0.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
10.
A sender's data link layer uses "bit stuffing" to
(a) avoid confusing data bits with control bits
(b) force the receiver to enlarge its flow control window
(c) pad the data so that it has an even length for parity calculations
(d) mark the start and the end of a frame
Correct answer is (a)
Your score on this question is: 0.00
Feedback:
See section 1.2.2 of the course notes.
1.
The point-to-point (PPP) protocol
can only be used in analog dial-up connections
is a data-link protocol
can only be used to carry IP over serial lines
(a) II only
(b) II and III only
(c) III only
(d) I and II only
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.5 of the course notes.
--------------------------------------------------------------------------------
2.
A specific CSMA-CD network such as 10-BASET "Ethernet"
(a) works best for an even number of nodes
(b) suffers performance degradation as nodes are added
(c) has higher cost per node as nodes are added
(d) can connect very distant nodes
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 1.2.4 of the course notes.
--------------------------------------------------------------------------------
3.
What is the type of an "8+1" parity code that outputs 100101011?
(a) Cannot tell since we do not know which bit is the parity bit
(b) Null Parity
(c) Odd Parity
(d) Even Parity
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
4.
Collision Detection improves the throughput of multiple access networks because
it can shorten the length of garbled frames
it can decrease the number of garbled frames
it delays by a random amount of time when a collision is detected
(a) I and II only
(b) II and III only
(c) I, II, and III
(d) I only
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.4 of the course notes.
--------------------------------------------------------------------------------
5.
A packet-switched network uses switches that schedule packets using a first-in-first-out (FIFO) discipline. Several people want to carry out a conference over this network. The conference is carried out via typed text for the most part, but, occasionally, one of the parties has to send a large video. This happens very rarely. Which of the following switching approaches is most suitable for this application?
(a) Circuit-switched
(b) Message-switched
(c) Space-switched
(d) Packet-switched
Correct answer is (d)
Your score on this question is: 10.00
Feedback:
See section 1.2.3 of the course notes.
--------------------------------------------------------------------------------
6.
A university has 20 computers in a laboratory that is currently served by several small 10 Base-T "Ethernet" hubs that are directly connected to each other. The network performance has been found to be lacking, and an upgrade is planned. The computers are identical and place a comparable load on the network that is relatively constant and modest for each computer (in the order of 500 Kbps). What would you suggest for the upgrade?
(a) Replace the hubs with 10 Base-T switches
(b) A new bank of dial-up modems
(c) A small 10 Base-T switch to connect the existing hubs
(d) Replace the hubs with 100 Base-T hubs
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.4 of the course notes.
--------------------------------------------------------------------------------
7.
When a student in Hong Kong uses her computer to have a voice conversation with a teacher in Pittsburgh, the application she uses requires that the network deliver bits at a modest but constant bit rate. This is because, even though voice can be faithfully encoded in less than 64 Kbps, the late arrival of a voice sample produces a noticeable and unpleasant sound effect. Which of the following switching options will give you better quality?
(a) Circuit-switched
(b) Message-switched
(c) Space-switched
(d) Packet-switched
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.3 of the course notes.
--------------------------------------------------------------------------------
8.
Which of the following are responsibilities of the data link layer?
Noticing transmission errors
Regulating transmission speed when a receiver is overwhelmed
Regulating transmission speed when any of several IP routers in a network path are overwhelmed
(a) I and II only
(b) I, II, and III
(c) I only
(d) II and III only
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.2 of the course notes.
--------------------------------------------------------------------------------
9.
The maximum binary data throughput of a cable that cleanly transmits a range of frequencies up to 100 MHz is
(a) within 80 and 120 megabits per second
(b) currently 56 Kbps but more as modem technology improves
(c) exactly 200 megabits per second
(d) exactly 200 megabytes per second
Correct answer is (c)
Your score on this question is: 10.00
Feedback:
See section 1.2.1 of the course notes.
--------------------------------------------------------------------------------
10.
In a broadcast-based network, longer propagation delays
(a) significantly decrease the benefit of sensing the carrier before transmitting
(b) do not affect the cost-benefit trade-off of carrier sensing
(c) make it all the more critical to sense the carrier before transmitting
(d) destroy the carrier, making it impossible to sense it before transmitting
Correct answer is (a)
Your score on this question is: 10.00
Feedback:
See section 1.2.6 of the course notes.
1.
Computer A has just received a TCP segment with a header that has the values 1500 and 1501 in the ACK and sequence number fields, respectively, from computer B. From this, we know that computer B is waiting for sequence number
(a) 1499
(b) 1501
(c) 1502
(d) 1500
Correct answer is (b)
Your score on this question is: 10.00
Feedback:
See section 2.1.3 of the course notes.
--------------------------------------------------------------------------------
2.
Which of the following apply to the transport protocol (e.g., TCP) but not to the network-layer protocol (e.g., IP)?
It need not be connection-oriented.
It cannot guarantee, by itself, that data is received completely and without errors.
It is only executed at the sender and receiver, not within the network infrastructure of routers and switches.