Chapter 2 Fundamentals Of Ethernet Lans

Question 1

What is IEEE

Answer 1

The institute of electrical and electronics engineers, they define the cabling, the connectors on the ends of the cables, the protocol rules, and everything else required to create an Ethernet LAN

Question 2

10BASE-T Name, speed, standard,length

Answer 2

Ethernet
10Mbps
802.3
100m (copper)

Question 3

100BASE-T Name, speed, standard,length

Answer 3

Fast Ethernet
100 Mbps
802.3u
100m (copper)

Question 4

1000BASE-LX Name, speed, standard,length

Answer 4

Gigabit Ethernet
1000 Mbps
802.3z
(Fiber) 5000 m

Question 5

1000BASE-T Name, speed, standard,length

Answer 5

Gigabit Ethernet
1000Mbps
802.3ab
100m (copper)

Question 6

10GBASE-T Name, speed, standard,length

Answer 6

10 Gig Ethernet
10 Gbps
802.3an
100m (copper)

Question 7

What kind of connector do Ethernet copper cables use

Answer 7

RJ-45

Question 8

UTP

Answer 8

Unshielded twisted pair. The most common type of ethernet cable

Question 9

EMI

Answer 9

Electromagnetic interference.

Question 10

What is it called when there is EMI between wire pairs in the same cable.

Answer 10

Crosstalk

Question 11

GBIC

Answer 11

Gigabit Ethernet Interface Converter. this is the original form factor for a removable transceiver for gigabit interfaces larger than SFPs(small form pluggable) supports speeds of 1 Gbps

Question 12

SFP

Answer 12

Small Form Pluggable. The replacement for GBICs used on a gigabit interface with a smaller size, taking up less space on the side of the networking card or switch . SFP supports speeds upto 4.25 Gbps

Question 13

SFP+

Answer 13

Small Form Pluggable Plus. It is the same size as the SFP but used on 10 Gbps interfaces.

Question 14

How many pairs of wires does 10BASE-T and 100BASE-T require to transfer data?

Answer 14

2 pairs

Question 15

How many pairs of wires does 1000BASE-T require to transfer data?

Answer 15

4 pairs

Question 16

What devices transmit on pins 1 and 2

Answer 16

Pc nics
Routers
Wireless APs

Question 17

What devices transmit on pins 3 and 6

Answer 17

Hubs

Switches

Question 18

What are the five layers of fiber cabling

Answer 18

Core
Cladding
Buffer
Strengthener 
Outer jacket

Question 19

What type of light does multi-mode fiber use

Answer 19

LED

Question 20

What type of light dose single mode fiber use

Answer 20

Laser

Question 21

True or false: you need two cables to transfer data with fiber . One for each direction

Answer 21

True.

Question 22

10GBASE-S type and distance

Answer 22

MM fiber 400m

Question 23

10GBASE-LX4 type and distance

Answer 23

MM fiber

300m

Question 24

10GBASE-LR type and distance

Answer 24

SM fiber

10km

Question 25

10GBASE-E type and distance

Answer 25

SM fiber | 30km

Question 26

Min and max of a PDU

Answer 26

46-1500 kb

Question 27

What does a data link header and trailer consist of

Answer 27

Header Preamble 7 - synchronization SFD (start frame delimiter) 1 - signifies that the next bite begins the destination Mac address field. Destination 6 - recipient Source 6 - sender Type 2 - ipv4 or ipv6 Trailer FCS(frame Check Sequence) 4 - error detection The data and pad in-between can vary between 46-1500 bytes

Question 28

What is a mac address

Answer 28

Media access control address . It is the hardcoded physical address on a nic. It is comprised of 6-bytes(or 48 bits) binary numbers, but it is usually displayed in a 12-digit hexadecimal number.

Question 29

What is an OUI

Answer 29

Organizationally unique identifier. It is a unique 3 byte code given by the IEEE. It is the first 3 bytes of a mac address . The last 3 are vendor assigned.

Question 30

Broadcast address

Answer 30

Frame sent to this address should be delivered to all devices on the ethernet LAN. It has a value of FFFF.FFFF.FFFF

Question 31

Multicast Address

Answer 31

frame sent to a multicast ethernet address will be copied and forwarded to a subset of the devices on the lan that volunteers to receive frames sent to a specific multicast address.

Question 32

Half duplex

Answer 32

The device must wait to send if it is currently receiving a frame. In other words it cannot send and receive at the same time.

Question 33

Full Duplex

Answer 33

Devices can send and receive that at the same time.

Question 34

CSMA/CD

Answer 34

Carrier sense multiple access with collision detection. This is an algorithm use with half duplex logic. A device with a frame to send listings until the ethernet is not busy. When the ethernet is not busy, the sender begins to send the frame. The sender listens while sending to discover whether a collision occurs. If this happens then the sender independently chooses a random time to wait before trying again to avoid unfortunate timing.

Question 35

What devices usually operate in half duplex

Answer 35

Hubs

Question 36

Which devices usually operate in full Duplex

Answer 36

Switches

Question 37

What device does the term Ethernet shared media refer to

Answer 37

Hubs