2. Fundamentals of Ethernet

Question 1

What is the standard name for 10Base-T

Answer 1

802.3

Question 2

What is the standard for 100Base-T

Answer 2

802.3u

Question 3

What is the standard for 1000Base-T

Answer 3

802.3ab

Question 4

What is the standard for 1000Base-LX

Answer 4

802.3z

Question 5

What is the max length for 1000Base-LX

Answer 5

5000m

Question 6

What is the max length for copper

Answer 6

100m

Question 7

What is the standard for 10GBase-T

Answer 7

802.3an

Question 8

What is the speed of SPF+

Answer 8

10Gbps

Question 9

Which pins are used in a 10BaseT/100BaseT straight through cable

Answer 9

1/2 3/6

Question 10

In a 10BaseT/100BaseT which pins does a switch transmit from

Answer 10

3 and 6

Question 11

Which devices transmit on pins 1,2

Answer 11

PC NICS
Routers
WAPs ethernet interface

Question 12

Which pins transmit on 3,6

Answer 12

Hubs and switches

Question 13

List the parts of a fiber optic cable

Answer 13

Core
Cladding
Buffer
Strengthener
Outer Jacket

Question 14

What is the light source called for fiber

Answer 14

optical transmitter

Question 15

How man cables do you need for a fiber connection

Answer 15

2 - 1 to transmit/receive on each end

Question 16

What are the standards and max distances for multimode fiber

Answer 16

10GBase-S 400m

10GBase-LX4 300m

Question 17

What are the standards and max distances for single mode fiber

Answer 17

10GBase-LR 10km

10GBase-E 30km

Question 18

Draw a standard ethernet frame

Answer 18

Preamble 7 btyes
SFD 1 byte
Destination 6 bytes
Source 6 bytes
Type 2 bytes
Data/Pad 46-1500bytes
FCS 4 bytes

Question 19

Describe the Preamble field in an Ethernet frame

Answer 19

7 bytes used for synchonrization

Question 20

Describe SFD in a Ethernet frame

Answer 20

Start Frame Delimiter
1 byte
Indicates next byte begins the destination MAC address

Question 21

What is the minimum and maximum size of the data inside an Ethernet frame

Answer 21

46 - 1500 bytes

Question 22

What is MTU

Answer 22

maximum transmission unit
max size of L3PDU inside the frame
1500bytes is largest IP MTU allowed over Ethernet

Question 23

What is the size of a MAC address

Answer 23

6 bytes (48bits / 12hex)

Question 24

What are the different parts of a MAC address

Answer 24

OUI

Vendor assigned

Question 25

What is the OUI

Answer 25

Orgazationally Unique Identifier 3 byte code handed out to manufacturers by IEEE First part of MAC address

Question 26

What are different names for MAC address(6)

Answer 26

``` LAN address Ethernet address Hardware address Burned in address Physical address universal address ```

Question 27

What is the Type field in an Ethernet frame used for

Answer 27

Identify L3PDU inside the frame | Usually IPv4 or IPv6

Question 28

What is the Type for IPv4 in Ethernet frame

Answer 28

x0800

Question 29

What is the Type for IPv6 in Ethernet frame

Answer 29

x86DD

Question 30

Does FCS provide error recovery

Answer 30

No, only error detection

Question 31

What is half duplex

Answer 31

Device must wait to send if its currently receiving a frame | Cannot send and receive at same time

Question 32

What does CSMA/CD stand for

Answer 32

Carrier Sense Multiple Access with Collision Detection

Question 33

What are the steps taken when a collision occurs

Answer 33

1. Sender listens when sending and sends jamming signal to all other nodes when collision has occurred. 2. They independently choose random time to wait before trying to send again 3. Listen to see if line is free

Question 34

What does Ethernet shared media mean

Answer 34

Designs that use hubs where CSMA/CD is required

Question 35

What term is used with a network built with only switches

Answer 35

Ethernet point-to-point

Question 36

What is the difference between multimode and single mode fiber

Answer 36

Multimode has multiple angles of light entering core Uses LED Single mode has smaller core (1/5 diameter or MM) Uses Laser

Question 37

What type of fiber connection is 1000Base LX

Answer 37

single mode

Question 38

What is the max length for 1000Base ZX

Answer 38

70km

Question 39

What type of connection is 1000Base ZX

Answer 39

single mode

Question 40

What type of connection is 1000Base LX4

Answer 40

multimode

Question 41

What is Ethernet point to point

Answer 41

A network built with only switches

Question 42

Draw a cross over cable

Answer 42

1 -3 2-6 3-1 6-2

Question 43

Draw a cross over cable for 1000Base-T

Answer 43

``` 1-3 2-6 3-1 4-7 5-8 6-2 7-4 8-5 ```