Understanding Network Types, Connections, and Protocols
Understanding Network Types and Connections
Network types depend on the geographical size they cover.
1. LAN (Local Area Network)
A LAN covers a single geographical area. Typically, all computers within a LAN belong to the same organization. LANs offer several benefits:
- Allow users to log in from any part of the organization.
- Enable easy data sharing.
- Help manage systems efficiently.
- Facilitate user collaboration.
2. WLAN (Wireless LAN)
A WLAN connects devices wirelessly. It requires special security measures to protect the network.
3. PAN (Personal Area Network)
A PAN connects devices to a computer, often for data transfer or synchronization. Common technologies used include Bluetooth and USB.
4. WAN and MAN
- MAN (Metropolitan Area Network): A MAN covers a large area, typically consisting of a series of connected LANs.
- WAN (Wide Area Network): A WAN covers even larger areas, connecting many computers and LANs together. VPNs (Virtual Private Networks) are often used within WANs.
5. SAN (Storage Area Network)
A SAN is dedicated to data storage and contains multiple hard disks. Storage is maintained in a single location, making data distribution, addition, and backup easier.
6. VPN (Virtual Private Network)
A VPN uses encryption to create an encrypted tunnel from a computer to a local network, ensuring secure communication.
7. VLAN (Virtual LAN)
A VLAN connects geographically separated computers, creating a virtual local network.
Network Connections
Network connections, whether wired or wireless, depend on factors such as distance between computers, bandwidth requirements, and cost.
Wired Connections
Fibre Optic Cables
Fibre optic cables transfer data using light beams, offering extremely fast speeds. They are more expensive but suffer less signal loss, making them ideal for high-speed backbone connections.
Cable Internet Access
Cable internet access provides broadband internet to homes, utilizing the existing cable television network. A cable modem converts data signals. This method offers high speed and reduces costs, although bandwidth can be reduced during peak usage times.
Dial-up
Dial-up is an older technology that connects computers using a standard telephone line. Computers must be connected to a modem. It is characterized by slow speeds and can be expensive.
Ethernet
Ethernet cables are commonly used in LANs to transfer data at high speeds over short distances.
Wireless Connections
WiMAX
WiMAX (Worldwide Interoperability for Microwave Access) is a wireless technology that transfers data over large distances. Bandwidth is high but decreases with distance. It can provide internet access to homes.
Wi-Fi (Wireless Fidelity)
Wi-Fi provides wireless connections in small areas. Wi-Fi devices connect to a wireless router, which then connects to the internet.
Bluetooth
Bluetooth is a wireless technology used for short-distance connections, typically in PANs.
3G and 4G
3G and 4G are wireless communication technologies that operate using mobile phone networks.
Measuring Network Speed
Bandwidth
Bandwidth refers to the amount of data that can be transferred at once, indicating the network’s capacity.
Communicating on Networks
MAC Addresses
A MAC (Media Access Control) address is a unique identifier built into a network interface card.
Protocol
A protocol is a set of rules about how to do something. Different technologies use different protocols.
IP (Internet Protocol)
IP defines how devices on a network are identified.
IP Address
An IP address uniquely identifies a computer on the network.
TCP (Transmission Control Protocol)
TCP ensures that data is sent and received correctly.
Ports
Ports represent services available on computers. Computers can offer different services through different ports.
Internet
The internet is a network of networks.
Data Routing
Data routing enables fast communication but does not guarantee 100% security.
Domain Names and DNS
URLs (Uniform Resource Locators) are used to identify computers on networks. They are generally short and easy to remember, while providing enough detail about the owner.
Internet Protocols
Hypertext Transfer Protocol (HTTP)
HTTP is used for communication between web servers and web browsers.
Hypertext Transfer Protocol Secure (HTTPS)
HTTPS encrypts data to provide secure communication.
Data Transfer Methods
Synchronous
In synchronous data transfer, the sender and receiver synchronize times and agree on a transfer rate, resulting in faster transfer processes.
Asynchronous
In asynchronous data transfer, the sender and receiver are not synchronized in terms of time.
Internet vs. Web
- Internet: The physical network of computers.
- Web: One of the services that runs on the internet.