Network Infrastructure and Domain Name System
This page explores the fundamental components of network infrastructure and the Domain Name System (DNS), which are crucial for the functioning of the internet.
Network Nodes and Routers
Vocabulary: Nodes are points on a network diagram, with routers being specialized nodes that direct data packets from one location to another.
Domain Name System (DNS)
The DNS is a hierarchical naming system for computers, services, or other resources connected to the internet. It translates human-readable domain names into IP addresses.
Example: The domain name "google.co.uk" corresponds to a specific IP address.
DNS Servers:
- 13 root DNS servers worldwide maintain a complete database of domain names and IP addresses
- Lower-level DNS servers, often owned by Internet Service Providers (ISPs), hold partial databases
- Requests are passed between servers until a match is found
Highlight: The DNS allows users to access websites using easy-to-remember names instead of numerical IP addresses, greatly enhancing the user experience of the internet.
Dynamic IP Addresses
Home devices typically use dynamic IP addresses, which can change when:
- The router reconnects to the internet
- A device is used in a different location (e.g., on holiday)
Network Interface Cards (NICs)
NICs are essential hardware components in networked devices:
- Built into every networked device
- Can be wireless (with an antenna) or wired (with a network cable socket)
- Often integrated into the motherboard of modern devices
Definition: A Network Interface Card (NIC) is a hardware component that enables a device to connect to a network, facilitating the sending and receiving of data.
Understanding these components and systems is crucial for comprehending how data is transmitted and accessed across the global internet infrastructure.