Network Cables

What is a twisted pair cable?

A cable that consist of several pairs of copper wire twisted around each other within an insulated jacket

What are the two types of twisted pair cables?

• Shielded twisted Pair (STP)

• Unshielded Twisted Pair (UTP)

What are the characteristics of STP?

An extra layer of braided foil shielding surrounds the wires to decrease electrical interference

What are the characteristics of UTP?

Has a PVC or plenum coating, but no outer foil shield to protect it from interference

• AKA Ethernet cable

What type of twisted pair cap was commonly used for networking?

Unshielded twisted pair is the most common

What are the different categories of twisted pair cables?

Category 5, Category 5e, Category 6, Category 6a, Category 7, Category 8

What are the characteristics of a Category 5e cable?

1 Gbps up to 100

What are the characteristics of a Category 6 cable?

10 Gbps up to 55m

What are the characteristics of a Category 6a cable?

10 Gbps up to 100m

• they go to cable

What are the characteristics of a Category 7 and 8 cables?

• 10 Gbps up to 100m (Cat 7 & 8)

• 25-40 Gbps up to 30m (Cat 8)

• Used in data centres

The two types of category 8 cables?

• Class I (Cat 8.1) = RJ45 connectors, backwards compatible

• Class 2 (Cat 8.2) = uses TERA connectors, not compatible with RJ45 installations

Maximum transmission distance for twisted pair cables?

100m is the max distance

Connector to landline phones mainly use?

RJ11 connector = two pairs (four wires)

What connector does a UTP use?

RJ45 = Four pairs (eight wires)

To standards were developed to ensure consistency in wiring?

T568A and T568B

Between the two standards, which one is more common?

T568B is more common in the US

What is the colour order for the T568A standard?

White / Green

Green

White / Orange

Blue

White / Blue

Orange

White / Brown

Brown

What is the colour order for the T568B standard?

White / Orange

Orange

White / Green

Blue

White / Blue

Green

White / Brown

Brown

What wire comes first in the T568A standard?

The green pair comes first, orange comes second

Maya comes first in the T568B standard?

The orange pair comes first, green pair is second

What is direct burial an what is used for?

Is a STP with an extra waterproof sheathing

• Used in situations where the network cable needs to be run outside or buried underground

What is a coaxial cable and what are its main uses?

A copper cable with a central conductor, insulating layer, metallic shield, and outer jacket

• The shield reduces electromagnetic interference

• Uses F type or BNC connectors

What is a plenum rated cable and why does it matter?

With fire-retardant jacket rated for use in plenum spaces

• The spaces above ceilings are blurry floors used for HVAC airflow

Why is fibre-optic being mean to electrical interference and wire tapping?

Because it uses pulses of light transmit data instead of electrical voltages

What are the layers of a fibre-optic cable from outside to inside?

Outer jacket, strength member, coating, cladding, core

What is single-mode fibre (SMF)?

Fibre optic cable with a very small call that carries a single ray of light

• Supports much longer distances and higher bands than multimode

• Use for WAN links, campus backbones, and telecoms

What is multimode fibre (MMF)?

Fibre optic cable with a larger core that carries multiple light modes simultaneously

• Shorter distance than single mode

• Light bounce off the cable walls as it travels through the cable, causes the signal to weak and more quickly

• Used to within buildings and data centres

What is the speed and distance for MMF?

Up to 400 Gbps for about 150 meters

• 1 Gbps for 1.2 miles

What is the speed and distance for SMF?

100 Gbps for up to 25 miles

• 1 Gbps up to 87 miles

• Dependent on the quality of cable and standard used

What mood would you use for long haul or Inter-building runs?

Single mode as it excels at long distance

What is a ST (straight tip) fibre connector?

A bayonet style fibre-optic connector that twist and locks into place like a BNC

• Common in legacy multi mode installations and some older networking equipment

What is an SC (subscriber connector) fibre connector?

A push-pool snap-in fibre optic connector, square in shape

• Single mode and multi mode applications

What is an LC (lucent connector)) fibre connector?

A small form-factor push-pull fibre connector, Half the size of SC and ST

• The most common connector in modern enterprise and data centre installations due to its compact size enabling high density

What is a RJ45 connector?

Registered Jack 45

• The standard eight – pin modular connector used to terminate ethernet (twisted pair) cables

• Used by Cat 5e, 6, 6a cables

What is a RJ11 connector?

Registered Jack 11

• A modular connector used for telephone lines and DSL connections

• Smaller than RJ45, only has six positions compared to RJ45’s 8

• Can be inserted into an RJ45 port but it will not function

What is an F-type connect?

A threaded coaxial connector to use for cable TV, satellite, and cable Internet

• Found on the back of cable modes, TVs and wall plates

What is a punch down block and what is a punch down tool?

• Punch Down Block = A wiring termination panel where individual wire pairs are punched down

• Punch Down Tool = Seats the wire and trims the excess in one motion