Chapter 2 - Wide Area Networks (WANs)

Question 1

WAN

Answer 1

Wide Area Network

Question 2

Typical WAN data transfer rate

Answer 2

1.5 Mbps to 6 Mbps

Question 3

PSTN

Answer 3

Public Switched Telephone Network

Question 4

ISP

Answer 4

Internet Service Provider

Question 5

How are analog signals measured?

Answer 5

In cycles per second, or Hertz.

Question 6

Hare are digital signals measured?

Answer 6

In bits per second (bps)

Question 7

bps

Answer 7

bits per second

Question 8

CO

Answer 8

Central Office

Question 9

Local Loop

Answer 9

The analog portion of voice circuit between the Central Office (CO) and the subscriber.

Question 10

DSO

Answer 10

Digital Signal Level Zero

Question 11

Digital Signal Level Zero (DSO)

Answer 11

The basic level of digital communication upon which all other digital signaling levels are built.

Question 12

Multiplexing

Answer 12

The process of combining several sets of signals onto a high-bandwidth transmission.

Question 13

Channel

Answer 13

A path for communication between two devices.

Question 14

Broadband

Answer 14

A transmission method in which the media bandwidth is allocated to multiple channels and each channel carries a separate signal.

Question 15

Baseband

Answer 15

LAN transmission methods using digital signals at speeds of 2 to 100 Mbps.

Question 16

Mbps

Answer 16

Megabits per second

Question 17

TDM

Answer 17

Time Division Multiplexing

Question 18

FDM

Answer 18

Frequency Division Multiplexing

Question 19

Two multiplexing technologies in use today:

Answer 19

Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM)

Question 20

DSH

Answer 20

Digital Signal Hierarchy

Question 21

Digital Signal Hierarchy (DSH)

Answer 21

A hierarchy established in North America to classify the speed capacity of multiplexing lines.

Question 22

What are the 5 Digital Signal Levels of the DSH?

Answer 22

DS0, DS1, DS2, DS3, & DS4

Question 23

Circuit switching

Answer 23

A technology that uses dedicated physical path to send and receive information.

Question 24

Patch switching

Answer 24

A technology that places addressing information into data packets, instead of relying upon a dedicated physical path.

Question 25

Name 4 circuite-switching WAN technologies

Answer 25

Plain Old Telephone Service (POTS), T1/E1, T3/E3, & ISDN.

Question 26

PADs

Answer 26

Packet assemblers/disassemblers

Question 27

Virtual circuits

Answer 27

A path between hosts that appears to be a discrete dedicated connection when in fact it is not. Describes connections between hosts in a packet-switching network.

Question 28

Name 4 packet-switching WAN technologies

Answer 28

Digital Subscriber Line (DSL), Cable modem, SONET, & ATM.

Question 29

modem (technical name for it)

Answer 29

modulator/demodulator

Question 30

What is a modem?

Answer 30

An analog device that enables computers to communicate over telephone lines by translating digital data into audio/analog signals (on the sending computer) and then back into digital form (on the receiving computer).

Question 31

What is the fastest possible speed for data transfer over a standard analog telephone line?

Answer 31

56 Kbps (Kilobits pers second)

Question 32

What is the difference between a traditional/analog modem and a modern modem?

Answer 32

Analog modems translates analog to digital while modern modems require no translations.

Question 33

IDSN

Answer 33

Integrated Services Digital Network

Question 34

What is a B Channel

Answer 34

Bearer Channel - 64 Kbps channels used in ISDNs for transmitting voice and data.

Question 35

What is a D Channel

Answer 35

Delta Channel - 16 Kbps channel used in ISDNs for signaling and call control.

Question 36

What is an Integrated Services Digital Network (IDSN)?

Answer 36

An international standard that defines the transmission of data, voice, and video over digital telephone lines at 64 Kbps. An IDSN line consists of several 64 Kbps channels, which can be combined for faster speeds.

Question 37

What are the 3 IDNS configurations?

Answer 37

2B+D (Basic Rate Interface or BRI), 23B+1D (Primary Rate Interface or PRI in the U.S. and Japan), & 30B+2B (Primary Rate Interface or PRI in Europe)