Lesson 3 - Chapter 3: Ethernet Cable Flashcards
What is the most common cable type for Ethernet and its sub types?
Twisted pair (2 sub-types: unshielded and shielded)
What’s the most common cable in use today and the one used for 10/100/1000/10GBaseT?
Unshielded Twisted Pair
(remember 10GBaseT = T = Twisted, UTP)
Twisted pair cabling consists of what gauge wires?
22 - 26 gauge wires twisted together into color-coded pairs
What does bandwidth mean?
the maximum speed at which data can be transferred
What UTP cable category is most used today? What are their Max speeds? (2)
Cat 6 or Cat 6a cables
Cat 6 = 1000 Mbps @ 100 meter segments, 10 Gbps @ 55 meter segments
Cat 6a = 10 Gbps @ 100 meter segments
What is crosstalk?
Crosstalk refers to the electromagnetic interference (EMI) that occurs when data travels through 2 adjacent cables
(affects the adjacent cable’s data)
What is STP?
Shielded twisted pairs of wires surrounded by an outer shield that protects from EMI
(rarely used)
What’s the difference between Cat 7 UTP and STP?
Cat 7 UTP = the shielding is around individual wire strands inside cable
STP = the shielding is around the outside of the bundle of wires inside the cable (protects from outside EMI sources like fluorescent lighting)
What’s the cable called that is designed to be buried outside? What type of cable is it?
- Direct burial cable
- A type of STP
What is a plenum space?
the space where most network cables go (above the ceiling, under the floors, and in the walls)
What is the protective sheathing for networking cables called?
the jacket
What are standard network cables made out of?
A plastic called PVC (polyvinyl chloride) that produces toxic fumes when burned
What is the type of cable that is fire-retardent that’s ideal to use in plenum spaces?
plenum-grade cable (has fire-retardent jacket)
What type of connector is used for Ethernet unshielded twisted-pair cable standard?
RJ-45
What are the 3 types of RJ connectors used for networking?
- RJ-11
- RJ-14
- RJ-45
What’s the difference between RJ-11 and RJ-14 connectors?
RJ-11 - single phone line, single twisted pair, 2 contact points
RJ-14 - 2 phone lines, 2 twisted pairs, 4 contact points
An RJ-45 connector has how many pairs of wires and contact points (wires)?
4 twisted pairs, 8 contact points
Can you use any RJ-45 connector on any Cat cable?
No, RJ-45’s aren’t interchangeable
(can’t use Cat 5e RJ-45 connector with a Cat 6 cable)
The attachment points for wires in an RJ connector are numbered from which direction?
from right to left (connector facing you)
What are the 2 standards for connecting an RJ-45 connector to a UTP cable?
- T568A
- T568B
Each twisted pair of wires in UTP have what standardized colors? (2)
a solid color wire and a white wire striped with that same solid color (candy cane)
How can you hook 2 computers directly together?
Use a special UTP cable called a crossover cable
What does a crossover cable look like?
its a standard UTP cable with one RJ-45 end using the T568A standard and the other RJ-45 end using the T568B standard so the signal reverses between them to send/receive.
(acts like a quick hub/switch)
How do fiber optic cables transmit data? (what type?) [2]
they use light (either LED or lasers)
Do fiber optic cables have the same issues as copper twisted pair?
No, they are immune to lightning, short circuits, EMI, etc
How far can fiber optic signals travel ideally?
2000 meters+
(compared to 100 meters on UTP)
Most fiber optic networks use what multimode cable?
62.5/125 multimode fiber optic cable
What are the 3 most common connectors used in fiber optic networks?
- ST (round)
- SC (square)
- LC (2 small squares)
fiber optic cables are half-duplex. What does that mean?
the data flows in one direction (so fiber optics need 2 cables to be bidirectional)
What is multi-mode fiber optic cabling?
it means multiple light signals are being transmitted at the same time using a different reflection angle within the core of the cable
Multi-mode fiber optic cabling is used with what type of light only?
LED
What’s a downside to multi-mode fiber optic cables?
the multiple reflection angles disperse over long distances and are only good for short distances
Network technologies that use single-mode fiber optic cabling use what kind of light?
laser light
(blazing high transfer rates over long distances, very rare to see in practice)
If you want to use fiber optic cabling, what 2 things do you need?
- fiber optic network card
- fiber optic switch
What distance do multimode cables top out at?
~600 meters
What’s the transmission speed difference between single-mode and multi-mode fiber optic cables?
multi-mode = 10-10,000 Mbps
single-mode = 100 Tbps over 100 miles (Terabits)
What cable did early versions of Ethernet run on?
coaxial cable
Where would you find coaxial cables today?
cable modems and satellite connections
How are coaxial cables rated?
rated using an RG number that measures its amount of impedence
What is impedance?
the resistance to the flow of an alternating current of electrical signal through a cable
What are the 2 types of connectors a coaxial cable uses?
- BNC connector (uncommon, looks like a water line)
- F-type connector (cable modems, most TVs)
What is the speed of a Cat 5 cable?
100 Mbps up to 100 meter segments
What is the speed of a Cat 5e cable?
1000 Mbps up to 100 meter segments
What is the speed of a Cat 6 cable?
1000 Mbps up to 100 meter segments, 10 Gbps networks up to 55 meter segments
What is the speed of a Cat 6a cable?
10 Gbps networks up to 100 meter segments
