Chapter 6: Data Communication

Question 1

Data Communication

Answer 1

Electronic transfer of data from one location to another

Question 2

Bandwidth

Answer 2

The amount of data that can be transferred from one point to another in a certain time period, usually one second

Question 3

Attenuation

Answer 3

Loss of power in a signal as it travels from the sending device to the receiving device

Question 4

Broadband (data transmission)

Answer 4

Multiple pieces of data are sent simultaneously to increase the transmission rate

Question 5

Narrowband

Answer 5

Voice-grade transmission channel capable of transmitting a maximum of 56,000 bps, so only a limited amount of information can be transferred

Question 6

3 Major components of a data communication systems

Answer 6

1) Sender and receiver devices
2) Modems (devices that connect a user to the Internet) or routers (connects network systems and controls their traffic flow)
3) Communication media (connect sender and receiver devices)

Question 7

Digital subscriber line (DSL)

Answer 7

A type of modem that uses ordinary phone lines

Question 8

Communication Media/Channels

Answer 8

Connect sender and receiver devices

• Either conducted: Physical path that signals are transmitted or
• Radiated: Uses antenna

Question 9

3 types of processing configurations

Answer 9

1) Centralized: One computer
2) Decentralized: Many computers
3) Distributed: Processing power is distributed among several locations

Question 10

Network Interface Card (NIC)

Answer 10

• Hardware component that enables computers to communicate over a network
• Also called adapter card

Question 11

3 Types of Networks

Answer 11

1) Local area network (LAN): Connects devices that are in close proximity
2) Wide area network (WAN): Spans serval cities, states, or countries and is owned by different parties
3) Metropolitan area network (MAN): Data communications for multiple organizations in a city or nearby cities

Question 12

Network Topologies

Answer 12

Represent a network’s physical layout, including the arrangement of computers and cables
- Types: Star, ring, bus, hierarchical, mesh

Question 13

Star Topology

Answer 13

Consists of a central computer (host computer or serve) and a series of nodes (workstations or peripheral devices)

Question 14

Ring Topology

Answer 14

• No host computer is required as each computer manages its own connectivity
• Each node is connected to two other nodes
• Transmission in one direction
• Needs less cable than star topology

Question 15

Bus Topology (linear bus)

Answer 15

Connects nodes along a network segment, but the ends of the cable are not connected, as they are in ring topology

Question 16

Hierarchical Topology (tree)

Answer 16

Combines computers with different processing strengths in different organizational levels

• Consists of the controller: Hardware and software device that controls data transfer from a computer to a peripheral device
• And the multiplexer: Hardware device that allows several nodes to share one communication channel

Question 17

Mesh Topology (plex/interconnected)

Answer 17

Every node is connected to every other node

- Known as plex or interconnected

Question 18

Protocols

Answer 18

Rules that govern data communication/information exchange

- Ex: Error detection, message length, and transmission speed

Question 19

Routing

Answer 19

The process of deciding which path data takes on a network.

• Usually determined by the type of network and the software used to transmit the data
• Routing table: Generated automatically by software and is used to determine the best possible route for a packet

Question 20

Packet

Answer 20

A collection of binary digits (including message data and control characters for formatting and transmitting) sent from computer to computer over a network

Question 21

2 types of routing

Answer 21

1) Centralized routing: One node is in charge of selecting the path for all packets. Stores routing table, does changes to a route
2) Distributed routing: Relies on each node to calculate its own best possible route. Each node contains its own routing tables

Question 22

Router

Answer 22

A network connection device containing software that connects network systems and controls their traffic flow
- Chooses the best path for packets

Question 23

2 Types of routers

Answer 23

1) Static: Require the network routing manager to give it information about which addresses are on which network
2) Dynamic: Build tables that identify addresses on each network

Question 24

Client/Server Model

Answer 24

Software runs on the local computer and communicates with the remote server to request information or services
- A server is a remote computer on the network that provides information or services in response to client requests

Question 25

Wireless network

Answer 25

A network that uses wireless instead of wired technology

Question 26

Mobile network (cellular network)

Answer 26

A network operating on a radio frequency (RF)

- Consists of radio cells, each served by a fixed transmitter, known as a cell site or base station

Question 27

Throughput

Answer 27

Similar to bandwidth, the amount of data transferred or processed in a specific time, usually one second

Question 28

Convergence

Answer 28

In data communication, refers to integrating voice, video, and data so that multimedia information can be used for decision making