Networks: LAN and WAN
Networks: LAN and WAN
Networks
- A network is a group of computer systems linked together. They may be linked by wired connections such as Ethernet cables, or wireless connections such as Wi-Fi or Bluetooth.
- Networks allow computers to share resources, such as files and printers, and to communicate with each other.
Local Area Network (LAN)
- A Local Area Network (LAN) is a network covering a small, localised area, such as a home, office, or school.
- LANs are usually owned and managed by a single organisation or individual.
- LANs can be wired (using Ethernet cables) or wireless (using Wi-Fi).
- Devices which make up a LAN are usually close together, often in the same building.
Wide Area Network (WAN)
- A Wide Area Network (WAN) covers a larger geographical area, often spanning cities or countries.
- WANs are typically made up of multiple LANs connected together.
- WANs are often owned and maintained by multiple organisations or service providers.
- The internet is the largest example of a WAN, connecting networks all over the globe.
Network Protocols
- Network protocols are sets of rules defining how devices on a network communicate and interact with each other.
- Some common protocols include HTTP (for web browsing), FTP (for file transfer), and SMTP (for email).
Wireless Networks
- Wireless networks use radio waves to transmit data between devices.
- They provide mobility and freedom from wires, but they can be less secure and more prone to interference than wired networks.
- Crucial for mobile device connectivity.
Network Security
- Networks, especially those connected to the internet, can be vulnerable to attacks, including hacking and viruses.
- Network security measures include firewalls, encryption, and secure password practices.
- Firewalls control traffic entering and leaving the network, blocking unauthorised access.
- Encryption converts data into a code to prevent unauthorised access.
Data Transmission
- Networks can use different methods to transmit data, these include serial, parallel, simplex, half-duplex, and full-duplex transmission.
- Understanding these transmission types is key to understanding network data flow.
Network Topologies
- The physical layout or arrangement of a network is referred to as its topology.
- Common topologies include Bus, Ring, Star and Mesh, each with their own advantages and disadvantages.