Modern Ethernet

Question 1

What are the two defining characteristics of Ethernet?

Answer 1

1 - Frame Size and elements

2- the way devices share access to the bus

Question 2

Difference between baseband and broadband

Answer 2

Baseband means only a single signal travels over a wire at one time
broadband means multiple signals travel over a wire at one time

Question 3

What does autosensing NIC, hub or switch do?

Answer 3

Determines both devices highest speeds

Question 4

10BaseFX summary

Answer 4

Speed 100 mbps
signal type baseband
distance 2km
node limit 1024
topology star bus (physcal star, logical bus)
used multimode fiber and SC or ST connector

Question 5

1000BaseT

Answer 5

Speed 1000 mbps
signal type baseband
distance 100km
node limit 1024
topology star bus (physcal star, logical bus)
Cat 5 or better

Question 6

1000BaseSX

Answer 6

• multimode fiber
• 850nm
• variable, commonly LC
• 220-500m

Question 7

1000BaseLX

Answer 7

• single-mode fiber
• 1300nm
• variable, commonly LC and SC
• 5 km

Question 8

What are SFF Connectors?

Answer 8

• Small form factor
• MT-RJ and LC
• most popular type of fiber connectors

Question 9

PC Connector?

Answer 9

• Physical contact connector
• two pieces of fiber touch when inserted
• replaced flat surface connectors

Question 10

UPC Connector?

Answer 10

• ultra physical contact connector
• polished extensively for a superior finish
• reduces signal loss over PC connectors

Question 11

APC Connector?

Answer 11

• angled physical contact connector
• add 8 degree angle
• lowers signal loss even further than UPC

Question 12

Standard for media converters?

Answer 12

Gigabit Interface Converter (GBIC)

Question 13

Smaller media converter?

Answer 13

Small Form-factor pluggable (SFP)

Question 14

10GBaseSR

Answer 14

850nm
LAN
multimode fiber
26-300m

Question 15

10GBaseSW

Answer 15

850nm
SONET/WAN
multimode fiber
26-300m

Question 16

10GBaseLR

Answer 16

1310nm
LAN
single-mode fiber
10km

Question 17

10GBaseLW

Answer 17

1310nm
SONET/WAN
single-mode fiber
10km

Question 18

10GBaseER

Answer 18

1550nm
LAN
single-mode fiber
40km

Question 19

10GBaseEW

Answer 19

1550nm
SONET/WAN
single-mode fiber
40km

Question 20

10GbE

Answer 20

• previously called 10GBaseT
• on cat 6 - 55 m
• on cat 6a - 100m

Question 21

What are MSAs

Answer 21

agreemtns among multiple manufacturers tomake interoperable devices and standards

Question 22

SFP+

Answer 22

• enchanced Small form factor pluggable

- media converter for 10 GbE

Question 23

What is WDM

Answer 23

• wave division multiplexing

- to differentiate wave signals on a single fiber

Question 24

What is BiDi?

Answer 24

• Bidirectional trasceivers
• have only a single optical port to send on one wavelength and receive on another
• costs less to deploy
• can use existing fiber runs to double the capacity of the network
• typically use SFP
• 40GBase use Quad Small Form-factor Pluggable (QSFP)

Question 25

How many pairs of wires do 10BaseT and 100BaseT use?

Answer 25

2

Question 26

What standard does IEEE 802.3ab describe?

Answer 26

1000BaseT

Question 27

Advantage of fiber?

Answer 27

not affected by EMI