Physical layer

Question 1

Characteristics of copper cabling

Answer 1

1. Inexpensive
2. Easy to install
3. Low resistance to electrical flow

Question 2

Copper cabling limitations and their mitigations

Answer 2

1. Attenuation - the longer the electrical signals have to travel the weaker the signal gets. Mitigated by having strict adherence to copper length limits
2. Electrical signal subject to interference to EMI and RFI and crosstalk. Mitigated by using metallic shielding and grounding. Crosstalk mitigated by twisting opposing circuit pair wires together.

Question 3

Characteristics of UTP

Answer 3

1. Twisted pairs able to mitigate crosstalk
2. Outer jacket protects wires from physical damage
3. Color coded insulation - isolates the pair of wires from each other and identifies each pair

Question 4

Characteristics of STP

Answer 4

1. Foil wrapped around wires and braided foil to mitigate EMI and RFI
2. Outer jacket protects copper wires from physical damage
3. Foil shield for each wire protects from EMI and RFI
4. Colour coded plastic insulation to isolate each pair of wires and identify the pairs
5. Better noise protection more expensive

Question 5

WHy is fibre optic better than copper

Answer 5

1. Longer distance at higher bandwidth
2. Less susceptible to attenuation and immune to RFI and EMI

Question 6

Fibre optic uses

Answer 6

1. Enterprise networks - used for interconnecting infrastructure devices
2. FTTH - provide always on broadband to homes
3. Long Haul networks - to connect cities and countries to one another
4. Submarine cable networks - provide reliable and high speed solutions capable of surviving sea conditions and able to travel cross ocean distance

Question 6

Fibre optic uses

Answer 6

1. Enterprise networks - used for interconnecting infrastructure devices
2. FTTH - provide always on broadband to homes
3. Long Haul networks - to connect cities and countries to one another
4. Submarine cable networks - provide reliable and high speed solutions capable of surviving sea conditions and able to travel cross ocean distance

Question 7

Wireless media limitations

Answer 7

1. Coverage area
2. Interference
3. Security
4. Shared medium - many users then low bandwidth