Module 2.1 - 2.4 Types of Cables Flashcards
Why are wires twisted in a twisted pair cable?
To reduce crosstalk.
What is the purpose of sheathing wires?
To further reduce crosstalk and to also protect against EMI.
Most cables contain how many twisted pairs?
4
What are some advantages of twisted pair cabling?
- Flexible
- Cost
- Ease of use
- New protocols are designed to to run on them.
What are some disadvantages of twisted pair cabling?
- Susceptible to inference and EMI
- Susceptible to eavesdropping.
What does UTP stand for?
Unshielded twisted pair
What does STP stand for?
Shielded twisted pair
What is the function of shielding wires in a STP?
- Reduce crosstalk
- Reduce EMI effects
- Used as a ground
- Increase conductivity/speed
What is a plenum space?
A part of a building that provides a pathway for the airflow needed by heating and air condition systems, such as above a dropped ceiling or below a raised floor.
What are plenum rated cables?
Cables that are fire resistant and non-toxic when burned.
When do you use plenum rated cables?
Designed for plenum spaces. These wires must be used since those spaces are a fire hazard. Can also be used for installations that run between floors.
When do you use riser cables?
Designed for installations that run between floors.
True or False:
Riser cables can be used in plenum spaces if plenum cables are unavailable.
False.
Riser cables should NEVER be used in plenum spaces. Only plenum rated cables should be used in plenum spaces.
Which cable should be used if you need a cable that has to be moved a lot, such as in a mobile setting?
A stranded cable as they are more flexible and less prone to break.
Which cable should be used in permanent or semi-permanent installations?
A solid cable since they carry signals better.
Which connector is used for phone cables?
RJ11.
What does a phone cable do?
A phone cable is used to connect a PC to a phone jack in a wall outlet to establish a dial-up internet connection. It is also used to connect a DSL modem to a telephone network. It has two pairs of twisted cable (a total of 4 wires).
Which kinds of cables use the RJ45 connecter?
Cat 3,5,5e,6,6a.
What kind of speed is a Cat 3 designed for?
10-megabit Ethernet (10Base-T) or 16-megabit token ring.
What kind of speed is a Cat 5 designed for?
Supports 100-megabit Ethernet(100BASE-TX) and ATM networking. Cat 5 specifications also support gigabit (1000 Mb) Ethernet. It does this by having more twists per inch than the Cat 3.
What’s the difference between Cat 5 and Cat 5e?
Cat 5e provides better EMI protection.
What is a Cat 6 designed for?
Supports 10-Gbps Ethernet (10GBASE-T) and high-bandwidth broadband communications. Most Cat 6 cables include a solid plastic core that keeps the cable from bending too much.
What is a Cat 6a designed for?
Provides better protection against EMI and crosstalk than the Cat 6. This provides better performance.
Which was ratified first? The Cat 6a or Cat 7?
The Cat 7 was ratified before that Cat 6a.
Which connector does the Cat 7 use?
GG45 TERA.
What is the difference between the Cat 7 and Cat 6a?
The Cat 7 requires shielding on EACH twisted pair AND the cable as a whole. It also has a difference connector.
How many connectors does the RJ11 have?
4, two pairs of wires.
What is the RJ11 primarily used for?
Telephone wiring.
What is the RJ45 primarily used for?
Ethernet and some token ring connections.
How many connectors does a RJ45 have?
8, four pairs of wires.
What’s the difference between a RJ45 and RJ48c?
The RJ48c is used for specific WAN connections such as a T1 line and is wired differently.
True or False:
The GG45 is backwards compatible with the RJ45.
True. It has four additional conductors in the corners of the connector that duplicate and replace the four inner pins on the RJ45.
True or False:
The TERA in compatible with the RJ45 and GG45.
False.
Which topology should you use when installing a coaxial cable?
A bus topology.
Name the layers to a coaxial cable.
- The inner conductor (made from copper or copper coated tin).
- The outer mech conductor or shield (made of aluminum or tin-coated copper)
- A PVC plastic insulator which surround the inner conductor and insulates the signal from the mesh conductor.
- A PVC plastic cable sheath, or jacket, that surrounds and protects the wire.
What are some advantages of coaxial cables?
Highly resistant to EMI.
Highly resistant to physical DMG.
What are some disadvantages of coaxial cables?
- More expensive.
- Inflexible (difficult to install).
- Unsupported by newer networking standards.
What grade of coaxial cabling is for a 10Base2 Ethernet networking (thinnet)?
RG-58
What is the resistance rating for a RG-58 grade coaxial cable?
50 ohms.
What is the use of a grade RG-59 coaxial cable?
Cable TV and cable networking.
What is the resistance rating for a RG-59 grade coaxial cable?
75 ohms
What is the use of a grade RG-6 coaxial cable?
Cable TB, satellite TV, and cable networking.
What is the resistance rating for a RG-6 grade coaxial cable?
75 ohms
True or False:
The RG-59 and RG-58 coaxial cables are interchangeable.
False. The resistance of ohms is different.
True or False:
The RG-59 and RG-6 coaxial cables are interchangeable.
True. The ohms are the same and they do basically the same thing.
What is a F-Type connector?
A threaded cable (or compression tool) used for cable and satellite TV connections. Also used to connect a cable modem to a broadband cable connection.
What is a BNC connector?
A connector that is molded into the cable. It’s used in 10Base2 Ethernet networks.
Which optic fiber is better for long distance, single or Multi?
Single is better for long distance.
What are some advantages to using fiber optics?
- Totally immune to EMI(electromagnetic interference).
- Highly resistant to eavesdropping.
- Supports extremely high data transmission rates.
- Allows greater cable distances without a repeater.
What are some disadvantages to fiber optics?
- Very expensive
- Difficult to work with.
- Special training required to attach connectors to cables.
What is a care of fiber optic cables made of?
Glass or plastic.
What are the parts of a fiber optic cable?
(From inside to out)
Core –> Cladding –> Sheathing
What does the cladding do in a fiber optic cable?
Maintains the signal in the center of the core as the cable bends.
What does sheathing do in a fiber optic cable?
Protects the cladding and assists in redirecting the light back to the center of the core.
What is the core diameter of a single mode fiber optic cable?
8-10.5 microns
What is the core diameter of a multi-mode fiber optic cable?
50-100 microns
How does light travel through a multi-mode fiber optic cable?
Multiple light streams enter at slightly different angles. This causes the light to reflect separately from each other, allowing multiple light streams through one cable.
Why does a multi-mode fiber optic cable have more trouble with distances than single-mode cables?
Because multiple streams of light are shot at different angles, thus increasing the amount of times the light is reflected inside the core. With each rebound, the light loses a small portion of energy, and because multi-mode angles the light to allow more streams, it increases the frequency of reflection, thus increasing the frequency of energy loss.
(Greater Modal dispersion).
What is the advantage of multi-mode fiber optics?
Higher light gathering capacity simplifies connections and allows lower-cost electronics. It also allows for a much higher amount of data to be transferred at one time.
Describe a ST Connector
- Used with single-mode and multi-mode cabling.
- Has a keyed bayonet-type connector.
- Also called a push-in and twist connector.
- Each wire has a separate connector.
- Nickel plated with a ceramic ferrule to ensure proper
core alignment and prevent light ray deflection. - Mnemonics are Set-and-Twist or Straight Tip.
Describe a SC Connector
- Used with single-mode and multi-mode cabling.
- Has a push-on/pull-off connector that uses a locking
tab to maintain connection. - Each wire has a separate connector.
- Uses a ceramic ferrule to ensure proper core
alignment and prevent light ray deflection. - Mnemonics are Set-and-Click or Square Connector.
Describe a LC Connector
- Used with single-mode and multi-mode cabling.
- Composed of a plastic connector with a locking tab
that is similar to a RJ45 connector. - A single connector with two ends keeps the two
cables in place. - Uses a ceramic ferrule to ensure proper core
alignment and to prevent light ray deflection. - Is half the size of other fiber optic connectors.
- Mnemonics are Lift-and-Click or Little Connector.
Describe a MTRJ Connector
- Used with single-mode and multi-mode cabling.
- Composed of a plastic connector with a locking tab.
- Uses metal guide pins to ensure that it is properly
aligned. - A single connector with one end holds both cables.
- Uses a ceramic ferrule to ensure proper core
alignment and prevent light ray deflection.
Describe a FC Connector
- Typically used with single-mode cabling.
- Each wire has a separate connector.
- Uses a threaded connector.
- Designed to stay securely connected in environments
where it may experience physical shock or intense
vibration.
What is WDM?
Stands for Wave Division Multiplexing. This joins several light wavelengths onto a single strand of fiber.
What is the advantage of WDM?
- This enables light signals in both directions across a
single fiber. - Today’s systems can easily multiplex 160 signals.
- WDM is mostly used by long-haul and high-speed
providers.
-Most WDM systems are designed to be used with
single-mode fiber.
