CSE4344 Final
9) The architecture of the Internet is comprised of which of the following? a) Single flat network. b) Layers. c) Centralized services. d) Distributed unconnected networks.
Layers
18) The sensitivity of a typical IEEE 802.15.4 device is on the order of -100dB. This means that the device can typically retrieve signals that are received at or above that signal to noise level but not below that level. If a transmitting device transmits at -100dB, what is the expected communication range to the receiver with - 100dB sensitivity? a) 0 meters. b) 1 meter. c) 10 meters. d) 100 meters.
a) 0 meters.
38) In the byte stuffing approach discussed in class, what is the maximum overhead that can be experienced by any one message? a) 100% b) 50% c) 25% d) 10%
a) 100%
11) The OSI layer model has how many more layers than the network layer model? a) 2 b) 3 c) 4 d) 5
a) 2
79) What is the bandwidth of a signal that ranges from 4 MHz to 7 MHz? a) 3 MHz b) 4 MHz c) 5 MHz d) All of the above e) None of the above
a) 3 MHz
13) What mechanism might the Data Link layer use for error control? a) ARQ b) ARP c) CSMA d) All of the above. e) None of the above.
a) ARQ
31) In the end-to-end argument, with regards to TCP/IP the Network Layer is assumed to provide a service that is which of the following? a) Connectionless b) Acknowledged communications c) Dynamic d) A virtual circuit
a) Connectionless
61) Which cipher mode leaves the general structure of the encrypted plaintext intact and visible to an eavesdropper? a) Electronic Code Book b) Cipher Block Chaining c) Stream Cipher d) Counter Mode
a) Electronic Code Book
75) Which of the following network types has the shortest potential delay? a) Fiber Optic Network b) Ethernet c) Sneaker Net d) Satellite
a) Fiber Optic Network
60) During congestion collapse, which of the following performance metrics is likely dropping precipitously? a) Goodput b) Throughput c) Slowdown d) All of the above. e) None of the above.
a) Goodput
56) Which of the following is an error correcting code? a) Hamming Code. b) Parity Bit. c) Checksum. d) CRC.
a) Hamming Code.
68) A time varying communication signal is composed of which of the following? a) Harmonics b) Bandwidth c) Receivers d) Transmitters
a) Harmonics
76) Where is a leaky bucket algorithm most likely implemented? a) Host sending data b) Network router c) DNS server d) Host receiving data
a) Host sending data
40) The data link (LINK) layer in the network layer model a) Is concerned with how to send finite-length messages between directly connected computers with specified levels of reliability. b) Specifies how to transmit bits across a medium. c) Is concerned with how to combine multiple links into networks and internetworks in order to send communication packets between distant nodes. d) Is concerned with how to send messages between applications located on the same computer
a) Is concerned with how to send finite-length messages between directly connected computers with specified levels of reliability
63) The advantages of a packet switched network include: a) No wasted network resources. b) Dedicated network resources. c) Constant end-to-end delays. d) All packets follow the same path.
a) No wasted network resources.
83) For which type of channel does the Shannon data rate formula define the theoretical maximum data rate? a) Noisy b) Noiseless c) Bandpass d) Low-pass
a) Noisy
1) What is the answer to the following riddle posed by Paul Mockapetris (as cited by Rose in 1993): What do you get when you cross a mobster with an international standard? a) Someone who makes you an offer that you can't understand. b) Someone who makes you an offer that you can't possibly read. c) Someone who makes you an offer that kills trees instead of people. d) Someone who makes you an offer that requires you to use a compliance committee to follow.
a) Someone who makes you an offer that you can't understand.
53) The efficiency of the Ethernet protocol improves when: a) The size of the Data payload is large. b) The maximum contention window size (CWmax) is very large. c) Fewer students surf the 'Net during class. d) The size of the Data payload is small.
a) The size of the Data payload is large.
78) Why are the wires twisted in a Twisted Pair? a) To minimize electromagnetic radiation from the wires. b) To keep the wires from separating during installation. c) To allow the medium to be full-duplex. d) All of the above. e) None of the above.
a) To minimize electromagnetic radiation from the wires.
99) In distance vector routing a) each router maintains a table giving the best known distance to each destination and the link to use to get there. b) each router shares its table with all routers on the network. c) converges quickly, but may suffer from a large table problem. d) All of the above. e) None of the above
a) each router maintains a table giving the best known distance to each destination and the link to use to get there.
7) Which of the following is a layer in the TCP/IP layer model? a) Internetwork. b) Session. c) Presentation. d) Physical.
a) internetwork
37) An upper-layer packet is split into 10 frames. If each of the frames has an 80% chance of arriving undamaged and if there is no error control (of any kind) performed at the data link layer, how many times must each frame be sent by the Link layer, on average, to send the entire packet to another machine? a) 0.107 b) 1 c) 9.3 d) 10.7
b) 1
43) Consider a message containing n blocks of plain text (P1, P2, . . . , Pi, . . . , Pn) that has been encrypted using AES in CBC mode. One bit of cipher text in block Ci is transformed from a 0 to a 1 during the transmission of block Ci. How many blocks of plaintext will be garbled as a result of this transmission error? a) 1 b) 2 c) n − i d) n − i + 1
b) 2
72) An upper-layer packet is split into 10 frames. If each of the frames has a 50% chance of arriving undamaged and if there is only ARQ performed at the Data Link layer, how many times must each frame be sent by the Data Link layer, on average, to send successfully the entire packet to another machine? a) 1 b) 2 c) 4 d) 8
b) 2
12) The OSI layer model has how many more layers than the TCP/IP layer model (Hint: the TCP/IP model and the network layer model used in class are not the same models.)? a) 2 b) 3 c) 4 d) 5
b) 3
65) What is the size in bits of an IPv4 address? a) 16 b) 32 c) 48 d) 128
b) 32
2) The network layer model has how many layers? a) 4 b) 5 c) 6 d) 7
b) 5
32) In the end-to-end argument, with regards to TCP/IP the Transport Layer is assumed to provide a service that is which of the following? a) Connectionless b) Acknowledged communications c) Dynamic d) A virtual circuit
b) Acknowledged communications
104) Services provided to the Transport Layer from the Network Layer should be designed to a) Make the routing technology apparent to the Transport Layer. b) Be independent of the router technology. c) Expose the number of the routers present in the network. d) Expose the topology of the routers present in the network.
b) Be independent of the router technology.
96) What does 'DNS' stand for? a) Domain Naming System b) Domain Name System c) Domain Numbering System d) Domain Number System
b) Domain Name System
36) The Gen2 RFID protocol utilizes which medium access control protocol? a) Binary Tree Walking b) Framed Slotted Aloha c) Reservation d) CSMA/CA
b) Framed Slotted Aloha
48) In which type of transmission is the channel capacity shared by both communicating devices at the same time? a) Automatic b) Full-duplex c) Half-duplex d) Simplex
b) Full-duplex
22) What is the transmission medium in a fiber optic cable? a) Air b) Glass c) Copper d) Aluminium
b) Glass
66) Which of the following encoding schemes allows for accurate clock recovery? a) Phase Shift Keying (PSK) b) Manchester c) Non-Return to Zero (NRZ) d) NRZ Invert (NRZI)
b) Manchester
21) ARPANET was developed with a broad range of objectives. Which of the following was a primary objective of the original ARPANET design? a) Security. b) Multiplexed utilization of interconnected networks. c) Accountability not required at the network level. d) Graphical user interfaces to the network functionality.
b) Multiplexed utilization of interconnected networks.
77) When a service level agreement is made between a host and its ISP, the host agrees to conform to certain constraints on sending data, and the ISP agrees to conform to certain constraints on delivering data to the host. A leaky bucket algorithm may be used to police both sides of the agreement. Where is a leaky bucket algorithm most likely implemented to police the agreement between the host and the ISP? [Hint: consider that two different leaky bucket algorithms need to be implemented and where the most likely location for both is.] a) Host sending data b) Network router c) DNS server d) Host receiving data
b) Network router
98) In a sliding window data link layer protocol, sending multiple frames in succession before an acknowledgement is received is known as which of the following? a) Broadcasting. b) Pipelining. c) Multicasting. d) Selective Repeat.
b) Pipelining.
81) What problem arises when too many packets arrive at a router in a short period of time? a) Transmission Delay b) Queuing Delay c) Propagation Delay d) All of the above. e) None of the above
b) Queuing Delay
106) IEEE 802.11 defines multiple communication rates. Why might multiple communication rates be beneficial? a) Only complex nodes will comply with the specification. b) Slower rates are more robust against errors. c) Communication speed limits vary based on municipality. d) All of the above e) None of the above
b) Slower rates are more robust against errors.
93) The physical (PHY) layer in the network layer model a) Is concerned with how to send finite-length messages between directly connected computers with specified levels of reliability. b) Specifies how to transmit bits across a medium. c) Is concerned with how to combine multiple links into networks and internetworks in order to send communication packets between distant nodes. d) Is concerned with how to send messages between applications located on the same computer.
b) Specifies how to transmit bits across a medium.
34) Consider the following scenario: the route for a packet or flow is calculated offline and then downloaded to all routers along the calculated path. What type of routing algorithm is described in this scenario? a) Dynamic routing b) Static routing c) Session routing d) Forwarding
b) Static routing
33) When an IEEE 802.11 node has a frame to send, it does what when it detects a busy medium? a) Continues to decrement its countdown timer b) Stops its countdown timer c) Goes to sleep d) Sends the frame immediately
b) Stops its countdown timer
73) When one or more harmonics are not recovered by the receiver a) The receiver recreates the missing harmonics. b) The recovered signal does not look like the original signal. c) The received harmonics allow the receiver to fully recover the original signal. d) The recovered signal is always decodable
b) The recovered signal does not look like the original signal.
58) Which word refers to the physical or logical arrangement of a network? a) Connection b) Topology c) Data Flow d) Mode of operation e) All of the above. f) None of the above.
b) Topology
24) What is the one word that defines the source of security in the cyber realm? a) Respect b) Trust c) Non-repudiation d) All of the above. e) None of the above
b) Trust
41) If you wanted a network that covered a city but nothing beyond the city, what kind of network would you use? a) LAN b) MAN c) WAN d) PAN
b) WAN
54) A platoon of Ewoks prepares to launch a surprise attack on an encampment of Storm Troopers. Given that there are 25 Ewoks, and assuming that each of them was born in the first half of the year, or the first 181 days of the year, what is the approximate probability that at least two Ewoks have the same birthday month and day? a) 0.5 b) 0.75 c) 0.81 d) 0.99
c) 0.81
6) In December of what year did the ARPANET network go live with four nodes? a) 1967 b) 1968 c) 1969 d) 1970
c) 1969
71) What frequency is commonly used for WiFi communications? a) 13.56 MHz b) 915 MHz c) 2.45 GHz d) 2.8 GHz
c) 2.45 GHz
102) In the DNS system, what is a poisoned cache? a) A cache that holds tracking cookies. b) A cache that holds malicious JavaScript. c) A cache that holds an intentionally false IP address. d) A cache that holds a false domain name.
c) A cache that holds an intentionally false IP address.
85) A host on the network sends a single packet to only the nearest member of a defined group on the network. This is an example of which of the following? a) Broadcast. b) Multicast. c) Anycast. d) All of the above. e) None of the above.
c) Anycast.
55) Which type of transmission impairment causes a signal to lose strength due to the resistance of the transmission medium? a) Distortion b) Noise c) Attenuation d) Decibel
c) Attenuation
92) Which equation(s) is(are) used to find the theoretical maximum data rate in a noisy channel? a) Shannon b) Nyquist c) Both Shannon and Nyquist d) None of the above.
c) Both Shannon and Nyquist
51) Which organization has authority over the rules and regulations governing wireless transmissions in the USA? a) ITU-T b) IEEE c) FCC d) IETF
c) FCC
10) If you are reading an RFC (Request For Comment), you are reading a document from which of the following organizations? a) ITU b) IEEE c) IETF d) NIST
c) IETF
The Network (NET) layer in the network layer model a) Is concerned with how to send finite-length messages between directly connected computers with specified levels of reliability. b) Specifies how to transmit bits across a medium. c) Is concerned with how to combine multiple links into networks and internetworks in order to send communication packets between distant nodes. d) Is concerned with how to send messages between applications located on the same computer.
c) Is concerned with how to combine multiple links into networks and internetworks in order to send communication packets between distant nodes.
59) In the OSI model, as the data packet moves from the lower layers to the upper layers headers are: a) Modified b) Rearranged c) Removed d) Added
c) Removed
95) IEEE 802.11 utilizes which of the following access protocols? a) Binary Tree Walking b) Framed Slotted Aloha c) Slotted Aloha d) CSMA/CD
c) Slotted Aloha
74) Which of the following network types has the greatest potential bandwidth? a) Fiber Optic Network b) Ethernet c) Sneaker Net d) Satellite
c) Sneaker Net
88) Which of the following network types has the greatest potential delay? a) Fiber Optic Network b) Ethernet c) Sneaker Net d) Satellite
c) Sneaker Net
3) Which of the following is a correct statement with regards to the TCP/IP layer model? a) The model is well-suited to describing any protocol stack, not just TCP/IP. b) The model clearly delineates the physical functionality and the data link functionality. c) The model does not clearly distinguish the concepts of services, interfaces, and protocols. d) All of the above. e) None of the above.
c) The model does not clearly distinguish the concepts of services, interfaces, and protocols.
17) The leaky bucket algorithm is used for a) Address resolution. b) Medium access control. c) Traffic shaping on the Internet. d) Connection establishment.
c) Traffic shaping on the Internet
14) What does UDP stand for? a) User Data Presentation b) User Directed Packets c) User Datagram Protocol d) User Distribution Process
c) User Datagram Protocol
42) If you wanted a network that covered a continent, what kind of network would you use? a) LAN b) MAN c) WAN d) PAN
c) WAN
82) Harmonics that go beyond the available bandwidth a) are brought back within the bandwidth limits. b) are recovered by examining the harmonics within the available bandwidth. c) are filtered out by the receiver. d) are designed to positively amplify signals beyond the bandwidth.
c) are filtered out by the receiver.
28) Given a noiseless wireless medium, what is the maximum number of levels a wireless signal could have? a) 1 b) 2 c) infinite d) Depends upon the data rate
c) infinite
46) What is the size in bits of an IPv6 address? a) 16 b) 32 c) 48 d) 128
d) 128
97) The processing delay in a router may be variable because a) Each packet is the same size. b) The router's user may be watching a video. c) IPv4 packets only are processed on the router. d) A CRC is calculated over the entire packet which may be of variable length.
d) A CRC is calculated over the entire packet which may be of variable length.
30) Which of the following networks might utilize Request to Send (RTS) and Clear to Send (CTS) frames? a) A LAN using CSMA/CD b) A LAN using MARS c) A LAN using RPR d) A LAN using CSMA/CA
d) A LAN using CSMA/CA
39) What is an HMAC? a) A hip-hop artist. b) A hash function used in the medium access control algorithm. c) A hash function used to create a digest of only a part of the message. d) A keyed hash function where the secret key is prepended to the message and then hashed with the message
d) A keyed hash function where the secret key is prepended to the message and then hashed with the message
100) Consider sending a packet from a source host to a destination host over a fixed route. The primary delay components in the end-to-end delay include which of the following? a) Processing Delay. b) Transmission Delay. c) Propagation Delay. d) All of the above. e) None of the above.
d) All of the above.
101) The network (NET) layer in the network layer model a) Deals with routing messages through a network. b) Utilizes internetwork-wide addresses. c) Does not utilize an acknowledged protocol. d) All of the above. e) None of the above
d) All of the above.
103) Which of the following modes of operation allow the ciphertext blocks to be decrypted in parallel? a) Counter b) ECB c) CBC d) All of the above. e) None of the above.
d) All of the above.
20) Which of the following are examples of distributed systems? a) DNS b) The World Wide Web c) email d) All of the above. e) None of the above.
d) All of the above.
23) A physical electromagnetic signal is created from the combination of several sinusoidal signals, each with different frequencies, amplitudes and phases. Which of the following is a reason why the original signal may not be faithfully recreated at a receiving node? a) Some of the frequencies may be filtered out by the receiving node. b) Noise may cancel some of the component signals. c) Noise may be combined with the other components resulting in distortion of the combined signal. d) All of the above. e) None of the above.
d) All of the above.
47) Which of the following is a significant problem in the use of one-time pads? a) One-time pad distribution b) One-time pad generation c) Secure storage of one-time pad d) All of the above. e) None of the above
d) All of the above.
62) Which of the following is a function of the Data Link layer? a) Dealing with transmission errors. b) Providing a well-defined service interface to the network layer. c) Regulating the flow of data so that slow receivers are not swamped by fast senders. d) All of the above. e) None of the above.
d) All of the above.
64) At the Network Layer, a connection oriented service a) Requires the setup of a Virtual Circuit. b) Forces all packets to follow the same route through the network. c) Requires each packet using the service to contain an identifier of which service it is using. d) All of the above. e) None of the above
d) All of the above.
8) Which of the following were nodes in the ARPANET when it went live? a) UCLA b) UCSB c) SRI d) All of the above. e) None of the above
d) All of the above.
84) The data link (LINK) layer in the network layer model a) Deals with point-to-point communications. b) Manages medium access control. c) Manages error control. d) All of the above. e) None of the above.
d) All of the above.
87) Which cipher mode XORs the output of the encryption function with the plain text to create the cipher text? a) Counter Mode b) Output Feedback Mode c) Stream Mode d) All of the above. e) None of the above
d) All of the above.
89) Which of the following may be used for error control in the Link Layer? a) Error detection code. b) Acknowledged communications. c) Connection oriented communications. d) All of the above. e) None of the above
d) All of the above.
91) In the use of a public key cipher in the communication from Alice to Bob, the use of Alice's private key in a private key operation followed by the use of Bob's public key in a public key operation results in which of the following security benefits? a) Nonrepudiation b) Integrity c) Confidentiality d) All of the above. e) None of the above.
d) All of the above.
16) In the cellular telephone network, protocols are defined to allow for the handoff of an active connection (i.e., an active phone call) as a handset moves from the range of one cell tower to within range of another cell tower. At which layer would such a handoff need to be defined in an IEEE 802.11 based network? a) Data Link layer. b) Network layer. c) Transport layer. d) Application layer.
d) Application layer.
4) What data/information is contained in the last 4 bytes in a Classic Ethernet frame? a) Data b) Frame length c) Message padding d) CRC
d) CRC
69) SHA-256 is an example of what type of algorithm? a) Public Key cipher b) Asymmetric Key cipher c) Symmetric Key cipher d) Hash algorithm
d) Hash algorithm
105) Variation in the delay in receiving a stream of packets is an example of which of the following? a) Noise. b) Attenuation. c) Collision. d) Jitter.
d) Jitter.
70) Which type of transmission impairment occurs when an outside source corrupts a signal? a) Attenuation b) Recruit c) Decibel d) Noise
d) Noise
44) For which type of channel does the Nyquist bit rate formula define the theoretical maximum bit rate? a) Bandpass b) Low-pass c) Noisy d) Noiseless
d) Noiseless
67) Which of the following is a network type that works within the radius of a human body only? a) LAN b) WAN c) MAN d) PAN
d) PAN
26) Which layer changes bits into electromagnetic signals? a) Session b) Data Link c) Network d) Physical
d) Physical
19) A network socket is used for which of the following? a) Tightening bolts. b) Connecting the application layer to the transport layer. c) Connecting the operating system to the physical hardware. d) Providing an abstract connection point for network communications between applications.
d) Providing an abstract connection point for network communications between applications.
57) When first beginning the transmission of data in a TCP communication, it is advised that the Transport layer of the sender determine the maximum rate at which segments are received at the receiver. Which of the following is a simple, and efficient, approach for determining this rate? a) Send a burst of fifty segments and determine how many segments are acknowledged before the resend timer goes off. b) Send a single packet and determine it's round trip time from the received acknowledgement packet. c) Send segments at a constant rate. d) Send a burst of five segments and average their received acknowledgement times.
d) Send a burst of five segments and average their received acknowledgement times.
90) What type of network is made of nodes that gather information about the state of the physical world and then wirelessly relay that information to a gateway? a) Internetworks b) WiFi c) Mesh Network d) Sensor Network
d) Sensor Network
86) Which network topology requires a central controller or hub? a) Mesh b) Bus c) Ring d) Star
d) Star
25) Which of the following is a computing device that is designed to connect multiple subnetworks? a) Server b) Ethernet c) Host d) Switch
d) Switch
49) Which of the following is a layer in the OSI model? a) Transport. b) Session. c) Presentation. d) All of the above. e) None of the above.
d) all of the above
5) In dynamic channel allocation for local area networks, carrier sense implies which of the following? a) a channel is busy b) the channel is wired c) ignorance of channel usage d) awareness of channel usage
d) awareness of channel usage
45) What are the two categories of transmission media used in computer networks? a) public and private media b) fast and slow media c) unsecured and secured media d) guided and unguided media
d) guided and unguided media
80) What is the name of the cipher type that consists of remapping each letter by another letter? a) one-time pad b) symmetric-key cipher c) asymmetric key cipher d) monoalphabetic substitution cipher
d) monoalphabetic substitution cipher