Wide Area Networks
Fibre Optic Backbone
- Connects various parts of a network
- Provides a path for exchanging information between LANs
- Backbone can be over: same building, different buildings, campus, or a wide area
- Fibre optic cabling used because of its speed and lack of attenuation
WAN
- LAN limited to small area and owned by a single organisation
- WAN (Wide Area Network) not confined to one area, can be owner by multiple
organisations
- Employes third parties (eg. public network telephone system) to provide connections
- Computer / devices can be spread around the world
Devices
Gateways
- Provide connectivity between two or more network segments
- Also called protocol converters
- Can operate at any network layer, usually between two different protocols
- A router can act as a gateway for a TCP/IP network by sending and receiving data on
the internet
- Router can see both MAC and IP addresses, but cannot repackage packets and
frames for another protocol
- A gateway is needed for a network with different protocols
, Transmission
- Transmission of radio waves discussed in previous chapter
- Radio waves used for: wireless transmission of sound, messages or information, or
communication with sea vessels and aircraft navigation
Satellite Radio Waves
- Satellite communications use satellite technology to provide voice calling, video
calling, internet, television, and radio channels
- Can span long distances
- Can operate under circumstances or conditions where other forms of communication
would be impossible
- Comprises of: transponder, antenna, communication payload, switching systems,
command, control system
- Features of satellite communications:
● Satellites usually in geostationary orbit
● Available globally (also at sea and over large distances)
● Very reliable
● Expensive set up and higher data costs
● More secure - used by the military
● Can provide weather information
● Services rarely fail during disasters
● High amount of data can be transmitted
Microwave
- Microwave link is a communications system
- Uses a beam of microwave frequency to transmit video, audio, or data
- Works between a few meters to several kilometers
Fibre Optic Backbone
- Connects various parts of a network
- Provides a path for exchanging information between LANs
- Backbone can be over: same building, different buildings, campus, or a wide area
- Fibre optic cabling used because of its speed and lack of attenuation
WAN
- LAN limited to small area and owned by a single organisation
- WAN (Wide Area Network) not confined to one area, can be owner by multiple
organisations
- Employes third parties (eg. public network telephone system) to provide connections
- Computer / devices can be spread around the world
Devices
Gateways
- Provide connectivity between two or more network segments
- Also called protocol converters
- Can operate at any network layer, usually between two different protocols
- A router can act as a gateway for a TCP/IP network by sending and receiving data on
the internet
- Router can see both MAC and IP addresses, but cannot repackage packets and
frames for another protocol
- A gateway is needed for a network with different protocols
, Transmission
- Transmission of radio waves discussed in previous chapter
- Radio waves used for: wireless transmission of sound, messages or information, or
communication with sea vessels and aircraft navigation
Satellite Radio Waves
- Satellite communications use satellite technology to provide voice calling, video
calling, internet, television, and radio channels
- Can span long distances
- Can operate under circumstances or conditions where other forms of communication
would be impossible
- Comprises of: transponder, antenna, communication payload, switching systems,
command, control system
- Features of satellite communications:
● Satellites usually in geostationary orbit
● Available globally (also at sea and over large distances)
● Very reliable
● Expensive set up and higher data costs
● More secure - used by the military
● Can provide weather information
● Services rarely fail during disasters
● High amount of data can be transmitted
Microwave
- Microwave link is a communications system
- Uses a beam of microwave frequency to transmit video, audio, or data
- Works between a few meters to several kilometers
