Transcript Terms - Wiley

Chapter 4 Terms
Data Communications and
Networking Considerations
Introduction to Information Systems
Judith C. Simon
Slide 4-1
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Slide 4-2
Chapter 4 Terms Review

Analog signal:
a continuous signal

Asynchronous communications:
one-character-at-a-time transmission of data

Bandwidth:
the range (highest minus lowest) of frequencies that can be
transmitted

Baud rate:
how fast signals can by sent over a communications
channel
Slide 4-3
Chapter 4 Terms Review

Bits per second (bps):
how fast data can be sent over a communications channel;
bps may be greater than the baud rate

Bridge:
hardware that connects two homogeneous (similar)
networks

Client/server model:
a system that includes at least one server—a computer that
provides a service to at least one other computer (a client);
often referred to as a distributed system
Slide 4-4
Chapter 4 Terms Review

Codec:
device that converts analog video and audio data into
digital signals

Common carrier:
an organization that provides a common type of
communications service to many people, such as telephone
service

Data communications:
use of a computer-based system to transmit data
electronically
Slide 4-5
Chapter 4 Terms Review

Data communications media:
means of transmitting data such as wire pairs, coaxial
cables, or microwave

Dedicated communications channel:
service in which the connection from one piece of
hardware to another is used only for that connection

Digital signal:
a discrete or pulse-type signal
Slide 4-6
Chapter 4 Terms Review

Full duplex:
a communications channel over which data transmissions
can travel in both directions simultaneously

Gateway:
hardware that connects heterogeneous (not similar)
networks

Half duplex:
a communications channel over which data transmissions
can travel in both directions, but not at the same time
Slide 4-7
Chapter 4 Terms Review

Latency:
amount of time required to get data from one point to
another

Local area networks (LAN):
computers linked into a network in a small geographic area
and widely used for sharing data, software, and hardware

Medium:
the means by which a transmission occurs, also referred to
as a channel; examples include wire pairs, coaxial cables,
optical fiber, and microwave
Slide 4-8
Chapter 4 Terms Review

Message:
a group of bits being transmitted

Middleware:
software that links client and server applications in
distributed systems

Modem:
device that converts digital data to analog (modulation)
and analog data to digital (demodulation)
Slide 4-9
Chapter 4 Terms Review

Network:
a group of computers and other hardware that is connected
by communications media so that resources can be shared

Network protocol:
rules for network communications; examples include
CSMA/CD, token passing and TCP/IP

Packet-switched service:
a type of communications service in which messages travel
in small groupings (packets) and may be relayed through
several computers before arriving at the destination
Slide 4-10
Chapter 4 Terms Review

Parallel communications:
use of multiple paths at one time to transmit bits of data

Receiver:
the recipient of data being communicated

Router:
device that selects the channel (route) to use for
transmission of a message

Sender
the originator of a message being communicated
Slide 4-11
Chapter 4 Terms Review

Serial communications:
use of one path to transmit bits of data

Simplex:
a communications channel over which data transmission
travels in one direction only

Synchronous communications:
transmission of a block of characters at a time rather than
one character at a time
Slide 4-12
Chapter 4 Terms Review

Telecommunications:
any communications over long distances, including those
by telephone or telegraph as well as by computer

Topology:
method of connecting computers in a network; examples
include fully interconnected, chain, loop, star, ring, and bus
Slide 4-13
Chapter 4 Terms Review

Value-added carrier:
organization that enhances the services of common carriers
(an added value) and sells the use of this capability

Wide area network (WAN):
computers linked into a network in a large geographic are
and widely used for sharing data, software and hardware
Slide 4-14
Slide 4-15