Congestion control is concerned with efficient use of a network at high load.
Answer:
Because the least-cost criterion is more flexible, it is more common than the
minimum-hop criterion.
Answer:
A modem is required to establish communication between a workstation and a server
over a public telephone network.
Answer:
Circuit switching and packet switching are traditional approaches to wide area network
design.
Answer:
More efficient use of bandwidth can be achieved if each signaling element represents
one bit.
Answer:
Real-time applications are more concerned with timing issues.
Answer:
Interactive applications such as remote logon and Web access are not sensitive to delay.
Answer:
With full-duplex operation a station can transmit and receive simultaneously.
Answer:
In a true multicast strategy the packet is replicated by routers only at branch points of
the spanning tree.
Answer:
The higher the data rate, the least cost-effective the transmission facility.
Answer:
In a star topology a repeater may also function as a device attachment point.
Answer:
Explicit congestion signaling approaches work forward but not backward.
Answer:
Transmission time is not proportional to the length of the frame.
Answer:
Soft-time applications have zero loss tolerance.
Answer:
Circuit switching remains one of the few effective technologies for long distance
communications.
Answer:
One simple approach to improving efficiency is to physically partition the LAN into
separate broadcast domains.
Answer:
The sine wave is the fundamental aperiodic signal.
Answer:
When a TCP entity detects the presence of congestion in the Internet, it reduces the
flow of data onto the Internet until it detects an easing in congestion.
Answer:
The ratio of data bits to total bits is called the code rate .
Answer:
FDMA is a technique used to share the spectrum among multiple stations.
Answer:
Switches and hubs form the basic building blocks of most local area networks.
Answer:
There is not a direct relationship between data rate and bandwidth.
Answer:
The popularity of wireless LANs has not grown significantly because the problems of
high prices, low data rates, occupational safety concerns, and licensing requirements
have not been addressed.
Answer:
The size of TCP’s send window can have a critical effect on whether TCP can be used
efficiently without causing congestion.
Answer:
It is not necessary for each host on a subnet to have an unique global internet address.
Answer:
The main task of the router is forwarding packets.
Answer:
Due to the large amounts of bandwidth available on modem networks, processing and
transmission overhead is a management issue and does not impair network efficiency.
Answer:
For 1 Gbps and 10 Gbps operations the CSMA/CD MAC protocol is used.
Answer:
Circuit switching is a transparent service.
Answer:
The characteristics and quality of a data transmission are determined both by the
characteristics of the medium and the characteristics of the signal.
Answer:
VoIP, streaming audio, and streaming video are not considered multimedia applications
because each involves a single media type.
Answer:
A static table is more flexible than a dynamic table in responding to both error and
congestion conditions.
Answer:
Scattering effects are difficult to predict.
Answer:
In a mobile environment one of the two antennas is moving relative to the other,
therefore the relative location of various obstacles moves also, so as not to hinder
transmission.
Answer:
In a protocol architecture, the transport protocol sits above application and other
upper-layer protocols, and just below the network or internetwork layer.
Answer:
Special cases of angle modulation are frequency modulation and ________ modulation.
A) VSB
B) repeat-accumulate
C) code rate
D) phase modulation
Answer:
An intermediary entity that acts as both a server and a client for the purpose of making
requests on behalf of other clients is the ____________ .
A) proxy server
B) registrar
C) redirect server
D) user agent
Answer:
The maximum utilization achievable using ALOHA can far exceed that of CSMA.
Answer:
MPLS is used to ensure that all packets in a particular flow take the same route over a
________.
A) label stack
B) backbone
C) tunnel
D) switched path
Answer:
An ________ uses Internet and Web technology in an isolated facility internal to an
enterprise.
A) application network
B) intranet
C) extranet
D) Internet portal
Answer:
In a ________ network, a dedicated communications path is established between two
stations through the nodes of the network. The telephone network is the most common
example.
A) frame relay
B) ATM
C) circuit switching
D) packet switching
Answer:
________ is generated by terminals. computers, and other data processing equipment
and then converted into digital voltage pulses for transmissions.
A) Voice
B) Audio
C) Binary data
D) Text
Answer:
The ________ updates the traffic control database used by the packet scheduler to
determine the service provided for packets of each flow.
A) admission control
B) management protocol
C) reservation protocol
D) routing protocol
Answer:
The simplest error-detecting scheme is to append a __________ bit to the end of
a block of data.
Answer:
Employees linking their computers into a temporary network in a conference room for a
meeting would be an example of ________ networking.
A) Nomadic
B) cross building interconnect
C) ad hoc
D) Lan extension
Answer:
A switching center that directly supports subscribers is known as ________.
A) a subscriber loop
B) a subscriber center
C) a branch exchange
D) an end office
Answer:
________ enables a receiver to regulate the flow of data from a sender so that the
receiver’s buffers do not overflow.
A) Flow control
B) Link control
C) Data control
D) Error control
Answer:
The central element of the star topology is a ________.
A) router
B) hub
C) subnetwork
D) switch
Answer:
When a data segment arrives that is in sequence, the receiving TCP entity has two
options concerning the timing of acknowledgment: Immediate and ________.
A) Cumulative
B) Controlled
C) Delayed
D) Non-responsive
Answer:
Defined in RFC 4340, __________ is an unreliable connection-oriented protocol that
can include mechanisms for detecting congestion by determining round-trip time and
packet drop rates.
A) TCP
B) RTT
C) DCCP
D) RTO
Answer:
One aspect of a reservation scheme is _______, in which a node in the network
monitors the traffic flow and compares it to the traffic contract.
A) traffic policing
B) window management
C) congestion control
D) RTT variance estimation
Answer:
Enterprises have formed ________ to reach customers, suppliers, and partners while
isolating their proprietary information from unwanted access.
A) intranets and extranets
B) internets and extranets
C) WANS and extranets
D) LANS and WANS
Answer:
A function performed by a receiving entity to limit the amount or rate of data that is
sent by a transmitting entity is ________.
A) flow control
B) error control
C) transmission control
D) data control
Answer:
The _______ packet confirms to receivers that a prolonged silence is due to departure
rather than network failure.
A) Note
B) RR
C) BYE
D) Timestamp
Answer:
________ is the determination of the willingness of the called party to engage in
communications.
A) User location
B) User availability
C) User capabilities
D) Session management
Answer:
Voice signals are transmitted over telephone lines at their original spectrum, which is
referred to as __________ transmission.
A) modulation
B) baseband
C) frequency
D) parity
Answer:
With __________ , the calling user supplies the phone number of a URI, which then
triggers a set of protocol interactions resulting in the placement of the call.
A) VoIP
B) PBX
C) RTP
D) SIP
Answer:
Bandwidth efficiency measures the efficiency with which bandwidth can be used to
transmit data.
Answer:
A _________ code takes an input of arbitrary length and produces a fixed-length CRC
check code.
A) BCH
B) LFS
C) VSB
D) CRC
Answer:
A ________ error can occur in the presence of white noise when a slight random
deterioration of the signal to noise ratio is sufficient to confuse the receiver’s decision of
a single bit.
A) burst
B) idle
C) single-bit
D) digital
Answer:
The relationship among the subcarriers in the OFDM scheme is referred
to as ________ .
A) modulation
B) B) subchannels
C) orthogonality
D) spread spectrum
Answer:
A set of options that use two physical links between nodes, one for transmission and
one for reception, is ________.
A) 100BASE-X
B) 100BASE-T
C) 100BASE-FX
D) 100BASE-TX
Answer:
The ________ is the most demanding service provided by ISA.
Answer:
A hop-by-hop option that is used to send IPv6 packets with payloads longer than 65,535
octets is ________.
A) PAD1
B) fragmentation
C) jumbo payload
D) PADN
Answer:
In __________ transmission systems, an error occurs when a binary 1 is transmitted
and a binary 0 is received, or a binary 0 is transmitted and a binary 1 is received.
A) analog
B) digital
C) parallel
D) none of the above
Answer:
To begin a connection establishment a TS user is in a ________ state.
A) CLOSED
B) LISTEN
C) OPEN
D) ESTAB
Answer:
A key parameter that characterizes any electromagnetic signal is ________, which is the
width of the range of frequencies that comprises the signal.
A) analog
B) wavelength
C) bandwidth
D) digital
Answer:
An error detecting code calculated from the remaining bits of the frame, exclusive of
flags, is the ________.
Answer:
The bridge provides an extension to the LAN once modifications to the
communications software in the stations attached to the LAN are made.
Answer:
A MPLS label is a 32-bit field consisting of the following elements: label value,
S, TTL, and ________.
Answer:
The ratio of redundant bits to data bits is called the ________ of the code.
Answer:
In a multipath environment, if the multiple versions of a signal arrive more than one
chip interval apart from each other, the receiver can recover the signal by correlating the
chip sequence with the dominant incoming signal. The remaining signals are treated as
noise. However, even better performance can be achieved if the receiver attempts to
recover the signals from multiple paths and then combine them with suitable delays.
This principle is used in the ________ receiver.
Answer:
Flexibility, resource sharing, robustness, and responsiveness are all advantages of
________ switching.
Answer:
In the TCP/IP architecture constituent networks are referred to as ________.
Answer:
An ________ extends a company’s intranet out onto the Internet to allow
selected customers, suppliers, and mobile workers to access the company’s private
data and applications.
Answer:
Three types of delays are: propagation delay, transmission time and ________ delay.
Answer:
________ uses multiple carrier signals at different frequencies, sending some of the bits
on each channel. The modem sends out test signals on each subchannel to determine the
signal-to-noise ratio. The modem then assigns more bits to channels with better signal
transmission and less bits to channels with poorer signal transmission.
Answer:
RSVP takes a ________, or connectionless, approach in which the reservation state is
cached information in the routers that is installed and periodically refreshed by end
systems.
Answer:
A ________ is a host or router that changes its point of attachment from one network or
subnetwork to another.
Answer:
The ratio of the power in a signal to the power contained in the noise that is present at a
particular point in the transmission is the ________ ratio.
Answer:
A layer of logic is added above the physical layer to achieve necessary control. This
logic is referred to as a ________ protocol.
Answer:
With internal ________ each packet is treated independently and packets intended for
the same destination may follow different routes.
Answer:
Stop-and-wait flow control is more efficient than sliding-window flow control.
Answer:
OFDM cannot overcome intersymbol interference in a multipath environment.
Answer:
Multiple signals, each at a different position on the spectrum, sharing the same
transmission medium, is known as frequency division ________.
Answer:
The topologies that have been used for LANs are ring, bus, tree, and ________.
Answer:
An optical transmission interface originally proposed by BellCore and standardized by
ANSI is ________. It is intended to provide a specification for taking advantage of the
high speed digital transmission capacity of optical fiber.
Answer: