Week 5 - POTS and Dial-Up and Broadband Connections and Fiber

Question 1

What is PSTN? What is it also called?

Answer 1

Public Switched Telephone Network

also called POTS

Question 2

What does modem stand for?

Answer 2

Modulator demodulator

Question 3

How does a dial-up modem work?

Answer 3

It transfers bits of data into audible wavelengths sent over POTS

Question 4

What is a baud rate?

Answer 4

baud rate is the measurement of how many bits can be passed across a phone line in a second

Question 5

What is broadband?

Answer 5

Broadband describes anything that isn’t a dial-up connection

Question 6

What are T-carrier technologies? Who invented it?

Answer 6

Invented by AT&T, it transmits multiple phone calls over a single link

Question 7

How many simultaneous phone call connections are there in a single T1 connection?

Answer 7

24

Question 8

What’s the transfer speed of a T1 connection?

Answer 8

1.544 megabits a second

Question 9

What’s the connection speed of an AT3/T3?

Answer 9

44.736 megabits per second

Question 10

What are DSLAMS?

Answer 10

Digital Subscriber Line Access Multiplexers

modems for DSL lines

Question 11

What does ADSL and SDSL stand for?

Answer 11

Asymmetrical digital subscriber lines

Symmetrical digital subscriber lines

Question 12

What is HDSL?

Answer 12

High bitrate digital subscriber line

has speeds over 1.544 mb/s

Question 13

What’s the difference between SDSL and ADSL?

Answer 13

ADSL - faster download, slower upload speed
SDSL - same download and upload speed

Question 14

How does cable broadband not interfere with TV broadcasts signals?

Answer 14

Cable broadband uses frequencies that don’t interfere with TV signals

Question 15

What type of cable is a coaxial cable?

Answer 15

shared bandwidth technology between users until it reaches ISPs core network

Question 16

What is a CO and what does a CO look like now?

Answer 16

CO is a building to which subscriber home/business lines are connected to on a local loop

CO now has automated hardware that handles this function

Question 17

What is a cable modem?

Answer 17

The cable modem device sits at the edge of the consumer network and connects it to the CMTS

Question 18

What connects CMTS to a consumer’s network?

Answer 18

cable modem

Question 19

What is CMTS?

Answer 19

cable modem termination system

connects different cable connections to an ISP’s core network

Question 20

What technology used CO? How was the bandwidth?

Answer 20

Central offices were/are used by dial-up and DSL connections and guaranteed a certain amount of bandwidth

Question 21

What is FTTX?

Answer 21

Fiber to the X, x can mean many things

Question 22

What is FTTN?

Answer 22

Fiber to the neighborhood

delivers fiber to a single cabinet for certain population

Question 23

What is FTTB?

Answer 23

fiber to the building/basement/business

twisted copper wires are used to connect everyone inside the building after

Question 24

What is FTTP?

Answer 24

fiber to the premises

FTTB and FTTH can be called FTTP

Question 25

What is ONT?

Answer 25

ONT is optical network terminator converts data from protocols the fiber networks use to something the twisted copper wires can understand

Question 26

What is FTTH?

Answer 26

Fiber to the home fiber to each individual home/apartment

Question 27

What does PPP stand for?

Answer 27

Point to Point Protocol

Question 28

what does CHAP stand for? (authentication)

Answer 28

Challenge Handshake Authentication Protocol

Question 29

What layer does PPP work on?

Answer 29

Data Link Layer

Question 30

What is PPP? Between how many linked devices?

Answer 30

The main function of PPP is to transport encapsulated L3 protocols over serial links (between 2 directly linked devices ONLY)

Question 31

What are the 4 PPP configuring options?

Answer 31

1. Multilink 2.Compression 3. Authentication 4. Error detection

Question 32

What are the 2 sub protocols for PPP on the network layer?

Answer 32

NCP network control protocol LCP link control protocol

Question 33

How is PPP data sent?

Answer 33

PPP data is encapsulated in a frame

Question 34

What do you call the demarcation point for fiber technologies?

Answer 34

ONT

Question 35

What is the NCP for PPP? What does it do?

Answer 35

Network Control Protocol NCP helps the router determine how to transport the encapsulated L3 protocols (NCP and LCP protocols control L3)

Question 36

What is the LCP for PPP? What 5 PPP configurations does it help with?

Answer 36

Link Control Protocol 1. auto start/ends connections for hosts link establishment 2. authentication 3. error detection 4. load balancing 5. multilink

Question 37

What does CHAP do?

Answer 37

CHAP is a 3 way handshake authentication that periodically confirms the client's identity Challenge Handshake Authentication Protocol

Question 38

What does PAP stand for? What does it do?

Answer 38

PAP stands for password authentication protocol uses passwords to validate users

Question 39

What does the Flag do in a PPP frame?

Answer 39

1 byte - lets receiver know this is the beginning of the frame (there may be a start/end flag)

Question 40

What does the Address field in a PPP frame contain?

Answer 40

1 byte - contains broadcast address

Question 41

What does the Control field in a PPP frame contain?

Answer 41

1 byte - allows a connectionless data link

Question 42

What does the Protocol field in a PPP frame contain?

Answer 42

1-3 bytes - identify network protocol of datagram

Question 43

What's the data size limit of a PPP frame?

Answer 43

1500 bytes per frame

Question 44

What does FCS stand for and what does it do?

Answer 44

Frame Check Sequence Makes sure that data was delivered/received intact without error

Question 45

What does PPPoE stand for?

Answer 45

Point-to-Point Protocol over Ethernet

Question 46

What does PPPoE do?

Answer 46

PPPoE encapsulates the PPP frame into an ethernet frame

Question 47

What authentication does PPPoE use most?

Answer 47

PPPoE uses (PAP) password authentication protocol the most

Question 48

What does it mean when something is multi-access enabled?

Answer 48

Multi-access means that every node connects to another

Question 49

What are 2 ways PPPoE is used?

Answer 49

1. PPPoE using DSL services from a DSL modem/router connecting to DSL 2. PPPoE DSL modem connected to PPPoE only router via ethernet cable

Question 50

What is the discovery stage in terms of PPPoE?

Answer 50

The discovery stage establishes a session ID to identify the hardware address

Question 51

Why is the discovery stage for PPPoE important?

Answer 51

The discovery stage ensures that data gets delivered to the right place

Question 52

What's the difference between PPP and PPPoE?

Answer 52

PPPoE is an extra layer of encapsulation for standard PPP frames, that allows data to be sent over ethernet connections