Wired Connections

All the ways we can connect computer together can be categorised as Wired or Wireless

  • Wired connections physically connect the computers together to transfer data
  • Wireless connections use radio frequencies to transfer data without a physical connection.

When picking or comparing connectivity methods we need to consider: Speed / Bandwidth, Range, Latency

Wired connections make use of cables and there are two main types: Copper Cables and Fibre-optic Cables.

Copper cables

Copper cables are the most common type of cable. Pulses of electricity are used to transmit data (as 1s and 0s).

  • Speed / Bandwidth: most wired copper connections used on a LAN will be capable of providing 100MB/s - 1GB/s bandwidth
  • Range: ~ 100m, after which the electrical signal will need to be repeated and re-amplified
  • Latency: Higher than that of a fibre-optic cable 

The most common copper cable used in networking is the CAT 5 / CAT 6 cable, which is often simply referred to as an Ethernet Cable. Copper cabling is most commonly used due to being inexpensive and having a wide compatability.

Fibre-optic Cables

Fibre-optic cables are becoming more common, especially in WANs. They use pulses of light to transmit data.

  • Speed / Bandwidth: capable of providing large amounts of bandwidth, greater than that of a copper cable.
  • Range: many miles. Due to total internet reflection, the light signals sent down a fibre-optic cable can travel many miles without error.
  • Latency: Less than that of a copper cable

They provide greater bandwidth, range and latency than copper cables, but are generally too expensive to be used on LANs. 

Broadband

Over the past 10 years Internet Service Providers (ISPs) have been upgrading their networks replacing copper cabling for fibre-optic cabling to provide higher performance broadband.

There are two approaches:

  • FTTC (Fibre to the Cabinet): Fibre-optic cabling is laid to the cabinet, and copper cabling is then used to connect the cabinet to the property
  • FTTP – Fibre to the Property: Fibre-optic cabling is laid to the cabinet, and fibre cable is laid from the cabinet to the property.

Fibre to the property is more expensive and is more likely to be used by business.


Included in the following specifications:
Edexcel GCSE Computer Science