Ch 8 Terms - WANs

Question 1

X.25

Answer 1

An analog packet-switched WAN technology optimized for reliable long-distance transmission at a maximum of 2 Mbps.

Question 2

ISDN

Answer 2

An international standard that uses PSTN lines to carry digital signals–often voice and data signals simultaneously.

Question 3

OC

Answer 3

An internationally recognized rating that indicates throughput rates for SONET connections.

Question 4

NSP

Answer 4

AT&T, Verizon, and Sprint are all examples of this type of provider.

Question 5

BPL

Answer 5

High-speed Internet access delivered over the electrical grid.

Question 6

ONU

Answer 6

In a passive optical network, the device near the customer’s premises that terminates a carrier’s fiber-optic cable connection and distributes signals to multiple endpoints via fiber-optic cable (FTTP).

Question 7

ATM

Answer 7

Relies on fixed packets, called cells, that each consists of 48 bytes of data plus a 5-byte header.

Question 8

CSU/DSU

Answer 8

The connection point for a T1 line at the customer’s site, often with a multiplexer.

Question 9

CIR

Answer 9

The guaranteed minimum amount of bandwidth selected when leasing a frame relay circuit.

Question 10

PTSN

Answer 10

The network of lines and carrier equipment that provides telephone service to most homes and businesses (POTS).

Question 11

NIU

Answer 11

The point at which PSTN-owned lines terminate at a customer’s premises, usually located at the demarc.

Question 12

DSLAM

Answer 12

A connectivity device located at a telecommunications carrier’s office that aggregates multiple digital subscriber lines and connects them to a larger carrier or to the Internet backbone.

Question 13

DSL

Answer 13

A dedicated WAN technology that uses advanced data modulation techniques to achieve extraordinary throughput over regular phone lines.

Question 14

OLT

Answer 14

A device located at the carrier’s endpoint of a passive optical network.

Question 15

E1

Answer 15

A digital carrier standard used in Europe that offers 30 channels and a maximum of 2.048 Mbps throughput.

Question 16

E3

Answer 16

A digital carrier standard used in Europe that offers 480 channels and a maximum of 34.368 Mbps throughput.

Question 17

T1

Answer 17

A digital carrier standard used in North America and most of Asia that provides 1.544 Mbps throughput and 24 channels for voice, data, video, or audio signals. Uses TDM over twisted pair, coax, or fiber.

Question 18

T3

Answer 18

A digital carrier standard used in North America and most of Asia that provides 44.736 Mbps throughput and 672 channels for voice, data, video, or audio signals. Uses TDM over fiber.

Question 19

FRAME RELAY

Answer 19

A digital packet-switched WAN technology which offers throughputs between 64 Kbps and 45 Mbps.

Question 20

SONET

Answer 20

A high-bandwidth WAN signaling technique that specifies framing and multiplexing techniques.

Question 21

PRI

Answer 21

A type of ISDN that uses 23 bearer channels and one 64 Kbps data channel, represented by the notation 23B+D.

Question 22

BRI

Answer 22

A variety of ISDN that uses two 64 Kbps bearer channels and one 16 Kbps data channel (2B+D).